Revert of SkScaledCodec class (patchset #35 id:680001 of https://codereview.chromium.org/1260673002/ )

Reason for revert:
breaking ubuntu bots

Original issue's description:
> SkScaledCodec class
>
> This class does scaling by using a scanlineDecoder.
> getScanlines and skipScanlines are used for y sampling,
> the swizzler is used for x sampling
>
> this class is currently only working for png and jpeg images
> I will update other Codec types to work soon
>
> For SkJpegCodec to implement width wise swizzling it now
> uses a swizzler. I ran performance tests on this change.
> Here are the performance test results:
> https://docs.google.com/a/google.com/spreadsheets/d/1D7-Q_GXD_dI68LZO005NNvb8Wq2Ee0wEBEPG72671yw/edit?usp=sharing
>
> BUG=skia:
>
> Committed: https://skia.googlesource.com/skia/+/0944100ac89f797714eeae0cf2875e2335ff52ee
>
> Committed: https://skia.googlesource.com/skia/+/d518ea7927f9f4e0ed5b4134d1b4f48243855a47
>
> Committed: https://skia.googlesource.com/skia/+/b157917507d4f7d2651f0aeb566d31603cc02240

TBR=scroggo@google.com,msarett@google.com,djsollen@google.com,mtklein@google.com,emmaleer@google.com
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Review URL: https://codereview.chromium.org/1285173003

10 files changed, 200 insertions, 634 deletions

diff --git a/src/codec/SkBmpStandardCodec.cpp b/src/codec/SkBmpStandardCodec.cpp
index 1dfd04ee21..08146fc3e4 100644
--- a/src/codec/SkBmpStandardCodec.cpp
+++ b/src/codec/SkBmpStandardCodec.cpp
@@ -237,7 +237,7 @@ bool SkBmpStandardCodec::initializeSwizzler(const SkImageInfo& dstInfo,
 
     // Create swizzler
     fSwizzler.reset(SkSwizzler::CreateSwizzler(config,
-            colorPtr, dstInfo, opts.fZeroInitialized, this->getInfo()));
+            colorPtr, dstInfo, opts.fZeroInitialized));
 
     if (NULL == fSwizzler.get()) {
         return false;
diff --git a/src/codec/SkCodec_libgif.cpp b/src/codec/SkCodec_libgif.cpp
index fa267e83e9..2e348cc856 100644
--- a/src/codec/SkCodec_libgif.cpp
+++ b/src/codec/SkCodec_libgif.cpp
@@ -444,12 +444,11 @@ SkCodec::Result SkGifCodec::onGetPixels(const SkImageInfo& dstInfo,
                     // Create the subset swizzler
                     swizzler.reset(SkSwizzler::CreateSwizzler(
                             SkSwizzler::kIndex, colorTable, subsetDstInfo,
-                            zeroInit, this->getInfo()));
+                            zeroInit));
                 } else {
                     // Create the fully dimensional swizzler
                     swizzler.reset(SkSwizzler::CreateSwizzler(
-                            SkSwizzler::kIndex, colorTable, dstInfo, 
-                            zeroInit, this->getInfo()));
+                            SkSwizzler::kIndex, colorTable, dstInfo, zeroInit));
                 }
 
                 // Stores output from dgiflib and input to the swizzler
diff --git a/src/codec/SkCodec_libpng.cpp b/src/codec/SkCodec_libpng.cpp
index 159aecd7ef..c94f371399 100644
--- a/src/codec/SkCodec_libpng.cpp
+++ b/src/codec/SkCodec_libpng.cpp
@@ -11,7 +11,6 @@
 #include "SkColorTable.h"
 #include "SkBitmap.h"
 #include "SkMath.h"
-#include "SkScaledCodec.h"
 #include "SkScanlineDecoder.h"
 #include "SkSize.h"
 #include "SkStream.h"
@@ -463,7 +462,7 @@ SkCodec::Result SkPngCodec::initializeSwizzler(const SkImageInfo& requestedInfo,
     // Create the swizzler.  SkPngCodec retains ownership of the color table.
     const SkPMColor* colors = get_color_ptr(fColorTable.get());
     fSwizzler.reset(SkSwizzler::CreateSwizzler(fSrcConfig, colors, requestedInfo,
-                    options.fZeroInitialized, this->getInfo()));
+            options.fZeroInitialized));
     if (!fSwizzler) {
         // FIXME: CreateSwizzler could fail for another reason.
         return kUnimplemented;
@@ -583,7 +582,8 @@ public:
 
     SkCodec::Result onStart(const SkImageInfo& dstInfo,
                             const SkCodec::Options& options,
-                            SkPMColor ctable[], int* ctableCount) override {
+                            SkPMColor ctable[], int* ctableCount) override
+    {
         if (!fCodec->rewindIfNeeded()) {
             return SkCodec::kCouldNotRewind;
         }
@@ -594,9 +594,7 @@ public:
 
         // Check to see if scaling was requested.
         if (dstInfo.dimensions() != this->getInfo().dimensions()) {
-            if (!SkScaledCodec::DimensionsSupportedForSampling(this->getInfo(), dstInfo)) {
-                return SkCodec::kInvalidScale;   
-            }
+            return SkCodec::kInvalidScale;
         }
 
         const SkCodec::Result result = fCodec->initializeSwizzler(dstInfo, options, ctable,
@@ -606,7 +604,7 @@ public:
         }
 
         fHasAlpha = false;
-        fStorage.reset(this->getInfo().width() * SkSwizzler::BytesPerPixel(fCodec->fSrcConfig));
+        fStorage.reset(dstInfo.width() * SkSwizzler::BytesPerPixel(fCodec->fSrcConfig));
         fSrcRow = static_cast<uint8_t*>(fStorage.get());
 
         return SkCodec::kSuccess;
@@ -645,11 +643,6 @@ public:
 
     bool onReallyHasAlpha() const override { return fHasAlpha; }
 
-    SkEncodedFormat onGetEncodedFormat() const override { 
-        return kPNG_SkEncodedFormat;
-    }
-
-
 private:
     SkAutoTDelete<SkPngCodec>   fCodec;
     bool                        fHasAlpha;
@@ -680,14 +673,12 @@ public:
         }
 
         if (!conversion_possible(dstInfo, this->getInfo())) {
-            return SkCodec::kInvalidConversion;    
+            return SkCodec::kInvalidConversion;
         }
 
         // Check to see if scaling was requested.
         if (dstInfo.dimensions() != this->getInfo().dimensions()) {
-            if (!SkScaledCodec::DimensionsSupportedForSampling(this->getInfo(), dstInfo)) {
-                return SkCodec::kInvalidScale;
-            }
+            return SkCodec::kInvalidScale;
         }
 
         const SkCodec::Result result = fCodec->initializeSwizzler(dstInfo, options, ctable,
@@ -699,7 +690,7 @@ public:
         fHasAlpha = false;
         fCurrentRow = 0;
         fHeight = dstInfo.height();
-        fSrcRowBytes = this->getInfo().width() * SkSwizzler::BytesPerPixel(fCodec->fSrcConfig);
+        fSrcRowBytes = dstInfo.width() * SkSwizzler::BytesPerPixel(fCodec->fSrcConfig);
         fGarbageRow.reset(fSrcRowBytes);
         fGarbageRowPtr = static_cast<uint8_t*>(fGarbageRow.get());
         fCanSkipRewind = true;
@@ -762,14 +753,6 @@ public:
 
     bool onReallyHasAlpha() const override { return fHasAlpha; }
 
-    bool onRequiresPostYSampling() override {
-        return true;
-    }
-
-    SkEncodedFormat onGetEncodedFormat() const override { 
-        return kPNG_SkEncodedFormat;
-    }
-
 private:
     SkAutoTDelete<SkPngCodec>   fCodec;
     bool                        fHasAlpha;
diff --git a/src/codec/SkCodec_libpng.h b/src/codec/SkCodec_libpng.h
index e8807499ea..890402200c 100644
--- a/src/codec/SkCodec_libpng.h
+++ b/src/codec/SkCodec_libpng.h
@@ -37,7 +37,6 @@ protected:
     SkEncodedFormat onGetEncodedFormat() const override { return kPNG_SkEncodedFormat; }
     bool onRewind() override;
     bool onReallyHasAlpha() const override { return fReallyHasAlpha; }
-
 private:
     png_structp                 fPng_ptr;
     png_infop                   fInfo_ptr;
@@ -53,6 +52,7 @@ private:
 
     SkPngCodec(const SkImageInfo&, SkStream*, png_structp, png_infop, int);
 
+
     // Helper to set up swizzler and color table. Also calls png_read_update_info.
     Result initializeSwizzler(const SkImageInfo& requestedInfo, const Options&,
                               SkPMColor*, int* ctableCount);
diff --git a/src/codec/SkCodec_wbmp.cpp b/src/codec/SkCodec_wbmp.cpp
index 3081a3bba9..6f98294fc6 100644
--- a/src/codec/SkCodec_wbmp.cpp
+++ b/src/codec/SkCodec_wbmp.cpp
@@ -9,7 +9,6 @@
 #include "SkCodecPriv.h"
 #include "SkColorPriv.h"
 #include "SkColorTable.h"
-#include "SkScaledCodec.h"
 #include "SkStream.h"
 #include "SkCodec_wbmp.h"
 
@@ -81,8 +80,8 @@ SkSwizzler* SkWbmpCodec::initializeSwizzler(const SkImageInfo& info,
         case kIndex_8_SkColorType:
         case kN32_SkColorType:
         case kGray_8_SkColorType:
-            return SkSwizzler::CreateSwizzler(SkSwizzler::kBit, ctable, info, opts.fZeroInitialized, 
-                                              this->getInfo());
+            return SkSwizzler::CreateSwizzler(
+                    SkSwizzler::kBit, ctable, info, opts.fZeroInitialized);
         default:
             return NULL;
     }
@@ -202,9 +201,7 @@ public:
             return SkCodec::kUnimplemented;
         }
         if (dstInfo.dimensions() != this->getInfo().dimensions()) {
-            if (!SkScaledCodec::DimensionsSupportedForSampling(this->getInfo(), dstInfo)) {
-                return SkCodec::kInvalidScale;
-            }
+            return SkCodec::kInvalidScale;
         }
 
         if (!valid_alpha(dstInfo.alphaType(), this->getInfo().alphaType())) {
@@ -223,16 +220,12 @@ public:
         fSwizzler.reset(fCodec->initializeSwizzler(dstInfo,
                 get_color_ptr(fColorTable.get()), options));
         if (NULL == fSwizzler.get()) {
-            return SkCodec::kInvalidConversion;
+            return SkCodec::kInvalidInput;
         }
 
         return SkCodec::kSuccess;
     }
 
-    SkEncodedFormat onGetEncodedFormat() const {
-        return kWBMP_SkEncodedFormat;
-    }
-
 private:
     SkAutoTDelete<SkWbmpCodec>   fCodec;
     SkAutoTUnref<SkColorTable>   fColorTable;
diff --git a/src/codec/SkJpegCodec.cpp b/src/codec/SkJpegCodec.cpp
index c094d50a3b..83656da42d 100644
--- a/src/codec/SkJpegCodec.cpp
+++ b/src/codec/SkJpegCodec.cpp
@@ -11,7 +11,6 @@
 #include "SkJpegUtility_codec.h"
 #include "SkCodecPriv.h"
 #include "SkColorPriv.h"
-#include "SkScaledCodec.h"
 #include "SkScanlineDecoder.h"
 #include "SkStream.h"
 #include "SkTemplates.h"
@@ -150,14 +149,6 @@ SkJpegCodec::SkJpegCodec(const SkImageInfo& srcInfo, SkStream* stream,
 {}
 
 /*
- * Return the row bytes of a particular image type and width
- */
-static int get_row_bytes(const j_decompress_ptr dinfo) {
-    int colorBytes = (dinfo->out_color_space == JCS_RGB565) ? 2 : dinfo->out_color_components;
-    return dinfo->output_width * colorBytes;
-
-}
-/*
  * Return a valid set of output dimensions for this decoder, given an input scale
  */
 SkISize SkJpegCodec::onGetScaledDimensions(float desiredScale) const {
@@ -267,10 +258,10 @@ bool SkJpegCodec::setOutputColorSpace(const SkImageInfo& dst) {
 }
 
 /*
- * Checks if we can natively scale to the requested dimensions and natively scales the 
- * dimensions if possible
+ * Checks if we can scale to the requested dimensions and scales the dimensions
+ * if possible
  */
-bool SkJpegCodec::nativelyScaleToDimensions(uint32_t dstWidth, uint32_t dstHeight) {
+bool SkJpegCodec::scaleToDimensions(uint32_t dstWidth, uint32_t dstHeight) {
     // libjpeg-turbo can scale to 1/8, 1/4, 3/8, 1/2, 5/8, 3/4, 7/8, and 1/1
     fDecoderMgr->dinfo()->scale_denom = 8;
     fDecoderMgr->dinfo()->scale_num = 8;
@@ -282,10 +273,7 @@ bool SkJpegCodec::nativelyScaleToDimensions(uint32_t dstWidth, uint32_t dstHeigh
         if (1 == fDecoderMgr->dinfo()->scale_num ||
                 dstWidth > fDecoderMgr->dinfo()->output_width ||
                 dstHeight > fDecoderMgr->dinfo()->output_height) {
-            // reset native scale settings on failure because this may be supported by the swizzler 
-            this->fDecoderMgr->dinfo()->scale_num = 8;
-            chromium_jpeg_calc_output_dimensions(this->fDecoderMgr->dinfo());
-            return false;
+            return fDecoderMgr->returnFalse("could not scale to requested dimensions");
         }
 
         // Try the next scale
@@ -325,7 +313,7 @@ SkCodec::Result SkJpegCodec::onGetPixels(const SkImageInfo& dstInfo,
     }
 
     // Perform the necessary scaling
-    if (!this->nativelyScaleToDimensions(dstInfo.width(), dstInfo.height())) {
+    if (!this->scaleToDimensions(dstInfo.width(), dstInfo.height())) {
         return fDecoderMgr->returnFailure("cannot scale to requested dims", kInvalidScale);
     }
 
@@ -393,47 +381,6 @@ public:
         , fOpts()
     {}
 
-    /*
-    * Return a valid set of output dimensions for this decoder, given an input scale
-    */  
-    SkISize onGetScaledDimensions(float desiredScale) override {
-        return fCodec->onGetScaledDimensions(desiredScale);
-    }
-
-    /*
-     * Create the swizzler based on the encoded format.
-     * The swizzler is only used for sampling in the x direction.
-     */
-
-    SkCodec::Result initializeSwizzler(const SkImageInfo& info, const SkCodec::Options& options) {
-        SkSwizzler::SrcConfig srcConfig;
-        switch (info.colorType()) {
-            case kGray_8_SkColorType:
-                srcConfig = SkSwizzler::kGray;
-                break;
-            case kRGBA_8888_SkColorType:
-                srcConfig = SkSwizzler::kRGBX;
-                break;
-            case kBGRA_8888_SkColorType:
-                srcConfig = SkSwizzler::kBGRX;
-                break;
-            case kRGB_565_SkColorType:
-                srcConfig = SkSwizzler::kRGB_565;
-                break;
-            default:
-                //would have exited before now if the colorType was supported by jpeg
-                SkASSERT(false);
-        }
-
-        fSwizzler.reset(SkSwizzler::CreateSwizzler(srcConfig, NULL, info, options.fZeroInitialized, 
-                                                   this->getInfo()));
-        if (!fSwizzler) {
-            // FIXME: CreateSwizzler could fail for another reason.
-            return SkCodec::kUnimplemented;
-        }
-        return SkCodec::kSuccess;
-    }
-
     SkCodec::Result onStart(const SkImageInfo& dstInfo, const SkCodec::Options& options,
                             SkPMColor ctable[], int* ctableCount) override {
 
@@ -454,23 +401,8 @@ public:
         }
 
         // Perform the necessary scaling
-        if (!fCodec->nativelyScaleToDimensions(dstInfo.width(), dstInfo.height())) {
-            // full native scaling to dstInfo dimensions not supported
-
-            if (!SkScaledCodec::DimensionsSupportedForSampling(this->getInfo(), dstInfo)) {
-                return SkCodec::kInvalidScale;
-            }
-            // create swizzler for sampling
-            SkCodec::Result result = this->initializeSwizzler(dstInfo, options);
-            if (SkCodec::kSuccess != result) {
-                SkCodecPrintf("failed to initialize the swizzler.\n");
-                return result;
-            }
-            fStorage.reset(get_row_bytes(fCodec->fDecoderMgr->dinfo()));
-            fSrcRow = static_cast<uint8_t*>(fStorage.get());
-        } else {
-            fSrcRow = NULL;
-            fSwizzler.reset(NULL);
+        if (!fCodec->scaleToDimensions(dstInfo.width(), dstInfo.height())) {
+            return SkCodec::kInvalidScale;
         }
 
         // Now, given valid output dimensions, we can start the decompress
@@ -501,16 +433,9 @@ public:
         if (setjmp(fCodec->fDecoderMgr->getJmpBuf())) {
             return fCodec->fDecoderMgr->returnFailure("setjmp", SkCodec::kInvalidInput);
         }
-        // Read rows one at a time
-        JSAMPLE* dstRow;
-        if (fSwizzler) {
-            // write data to storage row, then sample using swizzler         
-            dstRow = fSrcRow;
-        } else {
-            // write data directly to dst
-            dstRow = (JSAMPLE*) dst;
-        }
 
+        // Read rows one at a time
+        JSAMPLE* dstRow = (JSAMPLE*) dst;
         for (int y = 0; y < count; y++) {
             // Read row of the image
             uint32_t rowsDecoded =
@@ -527,17 +452,13 @@ public:
 
             // Convert to RGBA if necessary
             if (JCS_CMYK == fCodec->fDecoderMgr->dinfo()->out_color_space) {
-                convert_CMYK_to_RGBA(dstRow, fCodec->fDecoderMgr->dinfo()->output_width);
+                convert_CMYK_to_RGBA(dstRow, this->dstInfo().width());
             }
 
-            if(fSwizzler) {
-                // use swizzler to sample row
-                fSwizzler->swizzle(dst, dstRow);
-                dst = SkTAddOffset<JSAMPLE>(dst, rowBytes);
-            } else {
-                dstRow = SkTAddOffset<JSAMPLE>(dstRow, rowBytes);
-            }
+            // Move to the next row
+            dstRow = SkTAddOffset<JSAMPLE>(dstRow, rowBytes);
         }
+
         return SkCodec::kSuccess;
     }
 
@@ -545,7 +466,7 @@ public:
 // TODO (msarett): Make this a member function and avoid reallocating the
 //                 memory buffer on each call to skip.
 #define chromium_jpeg_skip_scanlines(dinfo, count)                           \
-    SkAutoMalloc storage(get_row_bytes(dinfo));                              \
+    SkAutoMalloc storage(dinfo->output_width * dinfo->out_color_components); \
     uint8_t* storagePtr = static_cast<uint8_t*>(storage.get());              \
     for (int y = 0; y < count; y++) {                                        \
         chromium_jpeg_read_scanlines(dinfo, &storagePtr, 1);                 \
@@ -563,16 +484,13 @@ public:
         return SkCodec::kSuccess;
     }
 
-    SkEncodedFormat onGetEncodedFormat() const override {
-        return kJPEG_SkEncodedFormat;
-    }
+#ifndef TURBO_HAS_SKIP
+#undef chromium_jpeg_skip_scanlines
+#endif
 
 private:
     SkAutoTDelete<SkJpegCodec> fCodec;
-    SkAutoMalloc               fStorage;    // Only used if sampling is needed
-    uint8_t*                   fSrcRow;     // Only used if sampling is needed
     SkCodec::Options           fOpts;
-    SkAutoTDelete<SkSwizzler>  fSwizzler;
 
     typedef SkScanlineDecoder INHERITED;
 };
@@ -584,7 +502,6 @@ SkScanlineDecoder* SkJpegCodec::NewSDFromStream(SkStream* stream) {
     }
 
     const SkImageInfo& srcInfo = codec->getInfo();
-
     // Return the new scanline decoder
     return SkNEW_ARGS(SkJpegScanlineDecoder, (srcInfo, codec.detach()));
 }
diff --git a/src/codec/SkJpegCodec.h b/src/codec/SkJpegCodec.h
index fac7d96075..62a5bbc4cf 100644
--- a/src/codec/SkJpegCodec.h
+++ b/src/codec/SkJpegCodec.h
@@ -110,13 +110,19 @@ private:
     bool setOutputColorSpace(const SkImageInfo& dst);
 
     /*
-     * Checks if we can natively scale to the requested dimensions and natively scales the 
-     * dimensions if possible
+     * Checks if we can scale to the requested dimensions and scales the dimensions
+     * if possible
      */
-    bool nativelyScaleToDimensions(uint32_t width, uint32_t height); 
+    bool scaleToDimensions(uint32_t width, uint32_t height);
+
+    /*
+     * Create the swizzler based on the encoded format
+     */
+    void initializeSwizzler(const SkImageInfo& dstInfo, void* dst, size_t dstRowBytes,
+            const Options& options);
 
     SkAutoTDelete<JpegDecoderMgr> fDecoderMgr;
-    
+
     friend class SkJpegScanlineDecoder;
 
     typedef SkCodec INHERITED;
diff --git a/src/codec/SkScaledCodec.cpp b/src/codec/SkScaledCodec.cpp
deleted file mode 100644
index e0158b6b4e..0000000000
--- a/src/codec/SkScaledCodec.cpp
+++ /dev/null
@@ -1,261 +0,0 @@
-/*
- * Copyright 2015 Google Inc.
- *
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-#include "SkCodecPriv.h"
-#include "SkScaledCodec.h"
-#include "SkStream.h"
-#include "SkWebpCodec.h"
-
-
-SkCodec* SkScaledCodec::NewFromStream(SkStream* stream) {
-    bool isWebp = SkWebpCodec::IsWebp(stream);
-    if (!stream->rewind()) {
-        return NULL;
-    }
-    if (isWebp) {
-        // Webp codec supports scaling and subsetting natively
-        return SkWebpCodec::NewFromStream(stream);  
-    }
-
-    SkAutoTDelete<SkScanlineDecoder> scanlineDecoder(SkScanlineDecoder::NewFromStream(stream));
-    if (NULL == scanlineDecoder) {
-        return NULL;
-    }
-
-    // wrap in new SkScaledCodec
-    return SkNEW_ARGS(SkScaledCodec, (scanlineDecoder.detach()));
-}
-
-SkCodec* SkScaledCodec::NewFromData(SkData* data) {
-    if (!data) {
-        return NULL;
-    }
-    return NewFromStream(SkNEW_ARGS(SkMemoryStream, (data)));
-}
-
-SkScaledCodec::SkScaledCodec(SkScanlineDecoder* scanlineDecoder)
-    : INHERITED(scanlineDecoder->getInfo(), NULL)
-    , fScanlineDecoder(scanlineDecoder)
-{}
-
-SkScaledCodec::~SkScaledCodec() {}
-
-// returns a scaled dimension based on the original dimension and the sampleSize
-// NOTE: we round down here for scaled dimension to match the behavior of SkImageDecoder
-static int get_scaled_dimension(int srcDimension, int sampleSize) {
-    if (sampleSize > srcDimension) {
-        return 1;
-    }
-    return srcDimension / sampleSize;
-}
-
-static SkISize best_scaled_dimensions(const SkISize& origDims, const SkISize& nativeDims, 
-                                      const SkISize& scaledCodecDims, float desiredScale) {
-    if (nativeDims == scaledCodecDims) {
-        // does not matter which to return if equal. Return here to skip below calculations
-        return nativeDims;
-    }
-    float idealWidth = origDims.width() * desiredScale;
-    float idealHeight = origDims.height() * desiredScale;
-
-    // calculate difference between native dimensions and ideal dimensions
-    float nativeWDiff = SkTAbs(idealWidth - nativeDims.width());
-    float nativeHDiff = SkTAbs(idealHeight - nativeDims.height());
-    float nativeDiff = (nativeWDiff + nativeHDiff) / 2;
-
-    // calculate difference between scaledCodec dimensions and ideal dimensions
-    float scaledCodecWDiff = SkTAbs(idealWidth - scaledCodecDims.width());
-    float scaledCodecHDiff = SkTAbs(idealHeight - scaledCodecDims.height());
-    float scaledCodecDiff = (scaledCodecWDiff + scaledCodecHDiff) / 2;
-
-    // return dimensions closest to ideal dimensions.
-    // If the differences are equal, return nativeDims, as native scaling is more efficient.
-    return nativeDiff > scaledCodecDiff ? scaledCodecDims : nativeDims;
-
-} 
-/*
- * Return a valid set of output dimensions for this decoder, given an input scale
- */
-SkISize SkScaledCodec::onGetScaledDimensions(float desiredScale) const {
-    SkISize nativeDimensions = fScanlineDecoder->getScaledDimensions(desiredScale);
-    // support scaling down by integer numbers. Ex: 1/2, 1/3, 1/4 ...
-    SkISize scaledCodecDimensions;
-    if (desiredScale > 0.5f) {
-        // sampleSize = 1
-        scaledCodecDimensions = fScanlineDecoder->getInfo().dimensions();
-    }
-    // sampleSize determines the step size between samples
-    // Ex: sampleSize = 2, sample every second pixel in x and y directions
-    int sampleSize = int(1 / desiredScale);
-
-    int scaledWidth = get_scaled_dimension(this->getInfo().width(), sampleSize);
-    int scaledHeight = get_scaled_dimension(this->getInfo().height(), sampleSize);
-
-    // Return the calculated output dimensions for the given scale
-    scaledCodecDimensions = SkISize::Make(scaledWidth, scaledHeight);
-
-    return best_scaled_dimensions(this->getInfo().dimensions(), nativeDimensions, 
-                                  scaledCodecDimensions, desiredScale);
-}
-
-// check if scaling to dstInfo size from srcInfo size using sampleSize is possible
-static bool scaling_supported(const SkImageInfo& dstInfo, const SkImageInfo& srcInfo,
-                              int* sampleX, int* sampleY) {
-    SkScaledCodec::ComputeSampleSize(dstInfo, srcInfo, sampleX, sampleY);
-    const int dstWidth = dstInfo.width();
-    const int dstHeight = dstInfo.height();
-    const int srcWidth = srcInfo.width();
-    const int srcHeight = srcInfo.height();
-     // only support down sampling, not up sampling
-    if (dstWidth > srcWidth || dstHeight  > srcHeight) {
-        return false;
-    }
-    // check that srcWidth is scaled down by an integer value
-    if (get_scaled_dimension(srcWidth, *sampleX) != dstWidth) {
-        return false;
-    }
-    // check that src height is scaled down by an integer value
-    if (get_scaled_dimension(srcHeight, *sampleY) != dstHeight) {
-        return false;
-    }
-    // sampleX and sampleY should be equal unless the original sampleSize requested was larger
-    // than srcWidth or srcHeight. If so, the result of this is dstWidth or dstHeight = 1.
-    // This functionality allows for tall thin images to still be scaled down by scaling factors.
-    if (*sampleX != *sampleY){
-        if (1 != dstWidth && 1 != dstHeight) {
-            return false;
-        }
-    }
-    return true;
-}
-
-// calculates sampleSize in x and y direction
-void SkScaledCodec::ComputeSampleSize(const SkImageInfo& dstInfo, const SkImageInfo& srcInfo,
-                                      int* sampleXPtr, int* sampleYPtr) {
-    int srcWidth = srcInfo.width();
-    int dstWidth = dstInfo.width();
-    int srcHeight = srcInfo.height();
-    int dstHeight = dstInfo.height();
-
-    int sampleX = srcWidth / dstWidth;
-    int sampleY = srcHeight / dstHeight;
-
-    // only support down sampling, not up sampling
-    SkASSERT(dstWidth <= srcWidth);
-    SkASSERT(dstHeight <= srcHeight);
-
-    // sampleX and sampleY should be equal unless the original sampleSize requested was
-    // larger than srcWidth or srcHeight.
-    // If so, the result of this is dstWidth or dstHeight = 1. This functionality
-    // allows for tall thin images to still be scaled down by scaling factors.
-
-    if (sampleX != sampleY){
-        if (1 != dstWidth && 1 != dstHeight) {
-
-            // rounding during onGetScaledDimensions can cause different sampleSizes
-            // Ex: srcWidth = 79, srcHeight = 20, sampleSize = 10
-            // dstWidth = 7, dstHeight = 2, sampleX = 79/7 = 11, sampleY = 20/2 = 10
-            // correct for this rounding by comparing width to sampleY and height to sampleX
-
-            if (get_scaled_dimension(srcWidth, sampleY) == dstWidth) {
-                sampleX = sampleY;
-            } else if (get_scaled_dimension(srcHeight, sampleX) == dstHeight) {
-                sampleY = sampleX;
-            }
-        }
-    }
-
-    if (sampleXPtr) {
-        *sampleXPtr = sampleX;
-    }
-    if (sampleYPtr) {
-        *sampleYPtr = sampleY;
-    }
-}
-
-// TODO: Implement subsetting in onGetPixels which works when and when not sampling 
-
-SkCodec::Result SkScaledCodec::onGetPixels(const SkImageInfo& requestedInfo, void* dst,
-                                           size_t rowBytes, const Options& options,
-                                           SkPMColor ctable[], int* ctableCount) {
-
-    if (options.fSubset) {
-        // Subsets are not supported.
-        return kUnimplemented;
-    } 
-
-    Result result = fScanlineDecoder->start(requestedInfo, &options, ctable, ctableCount);
-    if (kSuccess == result) {
-        // native decode supported
-        return fScanlineDecoder->getScanlines(dst, requestedInfo.height(), rowBytes);
-
-    }
-
-    if (kInvalidScale != result) {
-        // no scaling requested
-        return result;
-    }
-    
-    // scaling requested
-    int sampleX;
-    int sampleY;
-    if (!scaling_supported(requestedInfo, fScanlineDecoder->getInfo(), &sampleX, &sampleY)) {
-        return kInvalidScale;
-    }
-    // set first sample pixel in y direction
-    int Y0 = sampleY >> 1;
-
-    int dstHeight = requestedInfo.height();
-    int srcHeight = fScanlineDecoder->getInfo().height();
-    
-    SkImageInfo info = requestedInfo;
-    // use original height as scanlineDecoder does not support y sampling natively
-    info = info.makeWH(requestedInfo.width(), srcHeight);
-
-    // update scanlineDecoder with new info
-    result = fScanlineDecoder->start(info, &options, ctable, ctableCount);
-    if (kSuccess != result) {
-        return result;
-    }
-    
-    const bool requiresPostYSampling = fScanlineDecoder->requiresPostYSampling();
-
-    if (requiresPostYSampling) {
-        SkAutoMalloc storage(srcHeight * rowBytes);
-        uint8_t* storagePtr = static_cast<uint8_t*>(storage.get());
-        result = fScanlineDecoder->getScanlines(storagePtr, srcHeight, rowBytes);
-        if (kSuccess != result) {
-            return result;
-        }
-        storagePtr += Y0 * rowBytes;
-        for (int y = 0; y < dstHeight; y++) {
-            memcpy(dst, storagePtr, rowBytes);
-            storagePtr += sampleY * rowBytes;
-            dst = SkTAddOffset<void>(dst, rowBytes);
-        }
-    } else {
-        // does not require post y sampling
-        result = fScanlineDecoder->skipScanlines(Y0);
-        if (kSuccess != result) {
-            return result;
-        }
-        for (int y = 0; y < dstHeight; y++) {
-            result = fScanlineDecoder->getScanlines(dst, 1, rowBytes);
-            if (kSuccess != result) {
-                return result;
-            }
-            if (y < dstHeight - 1) {
-                result = fScanlineDecoder->skipScanlines(sampleY - 1);
-                if (kSuccess != result) {
-                    return result;
-                }
-            }
-            dst = SkTAddOffset<void>(dst, rowBytes);
-        }
-    }
-    return kSuccess;
-}
diff --git a/src/codec/SkSwizzler.cpp b/src/codec/SkSwizzler.cpp
index 44277614c6..b2b7f927ac 100644
--- a/src/codec/SkSwizzler.cpp
+++ b/src/codec/SkSwizzler.cpp
@@ -7,7 +7,6 @@
 
 #include "SkCodecPriv.h"
 #include "SkColorPriv.h"
-#include "SkScaledCodec.h"
 #include "SkSwizzler.h"
 #include "SkTemplates.h"
 #include "SkUtils.h"
@@ -20,116 +19,114 @@ SkSwizzler::ResultAlpha SkSwizzler::GetResult(uint8_t zeroAlpha,
     return (((uint16_t) maxAlpha) << 8) | zeroAlpha;
 }
 
-// samples the row. Does not do anything else but sampling
-static SkSwizzler::ResultAlpha sample565(void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src,
-        int width, int deltaSrc, int offset, const SkPMColor ctable[]){
-
-    src += offset;
-    uint16_t* SK_RESTRICT dst = (uint16_t*) dstRow;
-    for (int x = 0; x < width; x++) {
-        dst[x] = src[1] << 8 | src[0];
-        src += deltaSrc;
-    }
-    // 565 is always opaque
-    return SkSwizzler::kOpaque_ResultAlpha;
-}
-
 // kBit
 // These routines exclusively choose between white and black
 
 #define GRAYSCALE_BLACK 0
 #define GRAYSCALE_WHITE 0xFF
 
-
-// same as swizzle_bit_to_index and swizzle_bit_to_n32 except for value assigned to dst[x]
 static SkSwizzler::ResultAlpha swizzle_bit_to_grayscale(
-        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int dstWidth,
-        int deltaSrc, int offset, const SkPMColor* /*ctable*/) {
-
+        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int width,
+        int /*bitsPerPixel*/, const SkPMColor* /*ctable*/) {
     uint8_t* SK_RESTRICT dst = (uint8_t*) dstRow;
 
-    // increment src by byte offset and bitIndex by bit offset
-    src += offset / 8;
-    int bitIndex = offset % 8;
-    uint8_t currByte = *src;
-
-    dst[0] = ((currByte >> (7-bitIndex)) & 1) ? GRAYSCALE_WHITE : GRAYSCALE_BLACK;
-
-    for (int x = 1; x < dstWidth; x++) {
-        int bitOffset = bitIndex + deltaSrc;
-        bitIndex = bitOffset % 8;
-        currByte = *(src += bitOffset / 8);
-        dst[x] = ((currByte >> (7-bitIndex)) & 1) ? GRAYSCALE_WHITE : GRAYSCALE_BLACK;
+    // Determine how many full bytes are in the row
+    int bytesInRow = width >> 3;
+    int i;
+    for (i = 0; i < bytesInRow; i++) {
+        U8CPU currByte = src[i];
+        for (int j = 0; j < 8; j++) {
+            dst[j] = ((currByte >> (7 - j)) & 1) ? GRAYSCALE_WHITE : GRAYSCALE_BLACK;
+        }
+        dst += 8;
     }
 
+    // Finish the remaining bits
+    width &= 7;
+    if (width > 0) {
+        U8CPU currByte = src[i];
+        for (int j = 0; j < width; j++) {
+            dst[j] = ((currByte >> 7) & 1) ? GRAYSCALE_WHITE : GRAYSCALE_BLACK;
+            currByte <<= 1;
+        }
+    }
     return SkSwizzler::kOpaque_ResultAlpha;
 }
 
 #undef GRAYSCALE_BLACK
 #undef GRAYSCALE_WHITE
 
-// same as swizzle_bit_to_grayscale and swizzle_bit_to_n32 except for value assigned to dst[x]
 static SkSwizzler::ResultAlpha swizzle_bit_to_index(
-        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int dstWidth,
-        int deltaSrc, int offset, const SkPMColor* /*ctable*/) {
+        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int width,
+        int /*bitsPerPixel*/, const SkPMColor* /*ctable*/) {
     uint8_t* SK_RESTRICT dst = (uint8_t*) dstRow;
 
-    // increment src by byte offset and bitIndex by bit offset
-    src += offset / 8;
-    int bitIndex = offset % 8;
-    uint8_t currByte = *src;
-
-    dst[0] = ((currByte >> (7-bitIndex)) & 1);
-
-    for (int x = 1; x < dstWidth; x++) {
-        int bitOffset = bitIndex + deltaSrc;
-        bitIndex = bitOffset % 8;
-        currByte = *(src += bitOffset / 8);
-        dst[x] = ((currByte >> (7-bitIndex)) & 1);
+    // Determine how many full bytes are in the row
+    int bytesInRow = width >> 3;
+    int i;
+    for (i = 0; i < bytesInRow; i++) {
+        U8CPU currByte = src[i];
+        for (int j = 0; j < 8; j++) {
+            dst[j] = (currByte >> (7 - j)) & 1;
+        }
+        dst += 8;
     }
 
+    // Finish the remaining bits
+    width &= 7;
+    if (width > 0) {
+        U8CPU currByte = src[i];
+        for (int j = 0; j < width; j++) {
+            dst[j] = ((currByte >> 7) & 1);
+            currByte <<= 1;
+        }
+    }
     return SkSwizzler::kOpaque_ResultAlpha;
 }
 
-// same as swizzle_bit_to_grayscale and swizzle_bit_to_index except for value assigned to dst[x]
 static SkSwizzler::ResultAlpha swizzle_bit_to_n32(
-        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int dstWidth,
-        int deltaSrc, int offset, const SkPMColor* /*ctable*/) {
+        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int width,
+        int /*bitsPerPixel*/, const SkPMColor* /*ctable*/) {
     SkPMColor* SK_RESTRICT dst = (SkPMColor*) dstRow;
 
-    // increment src by byte offset and bitIndex by bit offset
-    src += offset / 8;
-    int bitIndex = offset % 8;
-    uint8_t currByte = *src;
-
-    dst[0] = ((currByte >> (7 - bitIndex)) & 1) ? SK_ColorWHITE : SK_ColorBLACK;
-
-    for (int x = 1; x < dstWidth; x++) {
-        int bitOffset = bitIndex + deltaSrc;
-        bitIndex = bitOffset % 8;
-        currByte = *(src += bitOffset / 8);
-        dst[x] = ((currByte >> (7 - bitIndex)) & 1) ? SK_ColorWHITE : SK_ColorBLACK;
+    // Determine how many full bytes are in the row
+    int bytesInRow = width >> 3;
+    int i;
+    for (i = 0; i < bytesInRow; i++) {
+        U8CPU currByte = src[i];
+        for (int j = 0; j < 8; j++) {
+            dst[j] = ((currByte >> (7 - j)) & 1) ? SK_ColorWHITE : SK_ColorBLACK;
+        }
+        dst += 8;
     }
 
+    // Finish the remaining bits
+    width &= 7;
+    if (width > 0) {
+        U8CPU currByte = src[i];
+        for (int j = 0; j < width; j++) {
+            dst[j] = ((currByte >> 7) & 1) ? SK_ColorWHITE : SK_ColorBLACK;
+            currByte <<= 1;
+        }
+    }
     return SkSwizzler::kOpaque_ResultAlpha;
 }
 
 // kIndex1, kIndex2, kIndex4
 
 static SkSwizzler::ResultAlpha swizzle_small_index_to_index(
-        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int dstWidth,
-        int bitsPerPixel, int offset, const SkPMColor ctable[]) {
+        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int width,
+        int bitsPerPixel, const SkPMColor ctable[]) {
 
-    src += offset;
     uint8_t* SK_RESTRICT dst = (uint8_t*) dstRow;
     INIT_RESULT_ALPHA;
     const uint32_t pixelsPerByte = 8 / bitsPerPixel;
-    const size_t rowBytes = compute_row_bytes_ppb(dstWidth, pixelsPerByte);
+    const size_t rowBytes = compute_row_bytes_ppb(width, pixelsPerByte);
     const uint8_t mask = (1 << bitsPerPixel) - 1;
     int x = 0;
     for (uint32_t byte = 0; byte < rowBytes; byte++) {
         uint8_t pixelData = src[byte];
-        for (uint32_t p = 0; p < pixelsPerByte && x < dstWidth; p++) {
+        for (uint32_t p = 0; p < pixelsPerByte && x < width; p++) {
             uint8_t index = (pixelData >> (8 - bitsPerPixel)) & mask;
             UPDATE_RESULT_ALPHA(ctable[index] >> SK_A32_SHIFT);
             dst[x] = index;
@@ -141,19 +138,18 @@ static SkSwizzler::ResultAlpha swizzle_small_index_to_index(
 }
 
 static SkSwizzler::ResultAlpha swizzle_small_index_to_n32(
-        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int dstWidth,
-        int bitsPerPixel, int offset, const SkPMColor ctable[]) {
+        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int width,
+        int bitsPerPixel, const SkPMColor ctable[]) {
 
-    src += offset;
     SkPMColor* SK_RESTRICT dst = (SkPMColor*) dstRow;
     INIT_RESULT_ALPHA;
     const uint32_t pixelsPerByte = 8 / bitsPerPixel;
-    const size_t rowBytes = compute_row_bytes_ppb(dstWidth, pixelsPerByte);
+    const size_t rowBytes = compute_row_bytes_ppb(width, pixelsPerByte);
     const uint8_t mask = (1 << bitsPerPixel) - 1;
     int x = 0;
     for (uint32_t byte = 0; byte < rowBytes; byte++) {
         uint8_t pixelData = src[byte];
-        for (uint32_t p = 0; p < pixelsPerByte && x < dstWidth; p++) {
+        for (uint32_t p = 0; p < pixelsPerByte && x < width; p++) {
             uint8_t index = (pixelData >> (8 - bitsPerPixel)) & mask;
             SkPMColor c = ctable[index];
             UPDATE_RESULT_ALPHA(c >> SK_A32_SHIFT);
@@ -168,75 +164,58 @@ static SkSwizzler::ResultAlpha swizzle_small_index_to_n32(
 // kIndex
 
 static SkSwizzler::ResultAlpha swizzle_index_to_index(
-        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int dstWidth,
-        int deltaSrc, int offset, const SkPMColor ctable[]) {
+        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int width,
+        int bytesPerPixel, const SkPMColor ctable[]) {
 
-    src += offset;
     uint8_t* SK_RESTRICT dst = (uint8_t*) dstRow;
-    INIT_RESULT_ALPHA;
+    memcpy(dst, src, width);
     // TODO (msarett): Should we skip the loop here and guess that the row is opaque/not opaque?
     //                 SkScaledBitmap sampler just guesses that it is opaque.  This is dangerous
     //                 and probably wrong since gif and bmp (rarely) may have alpha.
-    if (1 == deltaSrc) {
-        // A non-zero offset is only used when sampling, meaning that deltaSrc will be
-        // greater than 1. The below loop relies on the fact that src remains unchanged.
-        SkASSERT(0 == offset);
-        memcpy(dst, src, dstWidth);
-        for (int x = 0; x < dstWidth; x++) {
-            UPDATE_RESULT_ALPHA(ctable[src[x]] >> SK_A32_SHIFT);
-        }
-    } else {
-        for (int x = 0; x < dstWidth; x++) {
-            dst[x] = *src;
-            UPDATE_RESULT_ALPHA(ctable[*src] >> SK_A32_SHIFT);
-            src += deltaSrc;
-        }
+    INIT_RESULT_ALPHA;
+    for (int x = 0; x < width; x++) {
+        UPDATE_RESULT_ALPHA(ctable[src[x]] >> SK_A32_SHIFT);
     }
     return COMPUTE_RESULT_ALPHA;
 }
 
 static SkSwizzler::ResultAlpha swizzle_index_to_n32(
-        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int dstWidth,
-        int deltaSrc, int offset, const SkPMColor ctable[]) {
+        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int width,
+        int bytesPerPixel, const SkPMColor ctable[]) {
 
-    src += offset;
     SkPMColor* SK_RESTRICT dst = (SkPMColor*)dstRow;
     INIT_RESULT_ALPHA;
-    for (int x = 0; x < dstWidth; x++) {
-        SkPMColor c = ctable[*src];
+    for (int x = 0; x < width; x++) {
+        SkPMColor c = ctable[src[x]];
         UPDATE_RESULT_ALPHA(c >> SK_A32_SHIFT);
         dst[x] = c;
-        src += deltaSrc;
     }
     return COMPUTE_RESULT_ALPHA;
 }
 
 static SkSwizzler::ResultAlpha swizzle_index_to_n32_skipZ(
-        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int dstWidth,
-        int deltaSrc, int offset, const SkPMColor ctable[]) {
+        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int width,
+        int bytesPerPixel, const SkPMColor ctable[]) {
 
-    src += offset;
     SkPMColor* SK_RESTRICT dst = (SkPMColor*)dstRow;
     INIT_RESULT_ALPHA;
-    for (int x = 0; x < dstWidth; x++) {
-        SkPMColor c = ctable[*src];
+    for (int x = 0; x < width; x++) {
+        SkPMColor c = ctable[src[x]];
         UPDATE_RESULT_ALPHA(c >> SK_A32_SHIFT);
         if (c != 0) {
             dst[x] = c;
         }
-        src += deltaSrc;
     }
     return COMPUTE_RESULT_ALPHA;
 }
 
 static SkSwizzler::ResultAlpha swizzle_index_to_565(
-      void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int dstWidth,
-      int bytesPerPixel, int offset, const SkPMColor ctable[]) {
+      void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int width,
+      int bytesPerPixel, const SkPMColor ctable[]) {
     // FIXME: Support dithering? Requires knowing y, which I think is a bigger
     // change.
-    src += offset;
     uint16_t* SK_RESTRICT dst = (uint16_t*)dstRow;
-    for (int x = 0; x < dstWidth; x++) {
+    for (int x = 0; x < width; x++) {
         dst[x] = SkPixel32ToPixel16(ctable[*src]);
         src += bytesPerPixel;
     }
@@ -249,42 +228,29 @@ static SkSwizzler::ResultAlpha swizzle_index_to_565(
 // kGray
 
 static SkSwizzler::ResultAlpha swizzle_gray_to_n32(
-        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int dstWidth,
-        int deltaSrc, int offset, const SkPMColor ctable[]) {
+        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int width,
+        int bytesPerPixel, const SkPMColor ctable[]) {
 
-    src += offset;
     SkPMColor* SK_RESTRICT dst = (SkPMColor*)dstRow;
-    for (int x = 0; x < dstWidth; x++) {
-        dst[x] = SkPackARGB32NoCheck(0xFF, *src, *src, *src);
-        src += deltaSrc;
+    for (int x = 0; x < width; x++) {
+        dst[x] = SkPackARGB32NoCheck(0xFF, src[x], src[x], src[x]);
     }
     return SkSwizzler::kOpaque_ResultAlpha;
 }
 
 static SkSwizzler::ResultAlpha swizzle_gray_to_gray(
-        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int dstWidth,
-        int deltaSrc, int offset, const SkPMColor ctable[]) {
-
-    src += offset;
-    uint8_t* SK_RESTRICT dst = (uint8_t*) dstRow;
-    if (1 == deltaSrc) {
-        memcpy(dstRow, src, dstWidth);
-    } else {
-        for (int x = 0; x < dstWidth; x++) {
-            dst[x] = src[0];
-            src += deltaSrc;
-        }
-    }
+        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int width,
+        int bytesPerPixel, const SkPMColor ctable[]) {
+    memcpy(dstRow, src, width);
     return SkSwizzler::kOpaque_ResultAlpha;
 }
 
 static SkSwizzler::ResultAlpha swizzle_gray_to_565(
-        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int dstWidth,
-        int bytesPerPixel, int offset, const SkPMColor ctable[]) {
+        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int width,
+        int bytesPerPixel, const SkPMColor ctable[]) {
     // FIXME: Support dithering?
-    src += offset;
     uint16_t* SK_RESTRICT dst = (uint16_t*)dstRow;
-    for (int x = 0; x < dstWidth; x++) {
+    for (int x = 0; x < width; x++) {
         dst[x] = SkPack888ToRGB16(src[0], src[0], src[0]);
         src += bytesPerPixel;
     }
@@ -294,14 +260,13 @@ static SkSwizzler::ResultAlpha swizzle_gray_to_565(
 // kBGRX
 
 static SkSwizzler::ResultAlpha swizzle_bgrx_to_n32(
-        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int dstWidth,
-        int deltaSrc, int offset, const SkPMColor ctable[]) {
+        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int width,
+        int bytesPerPixel, const SkPMColor ctable[]) {
 
-    src += offset;
     SkPMColor* SK_RESTRICT dst = (SkPMColor*)dstRow;
-    for (int x = 0; x < dstWidth; x++) {
+    for (int x = 0; x < width; x++) {
         dst[x] = SkPackARGB32NoCheck(0xFF, src[2], src[1], src[0]);
-        src += deltaSrc;
+        src += bytesPerPixel;
     }
     return SkSwizzler::kOpaque_ResultAlpha;
 }
@@ -309,58 +274,54 @@ static SkSwizzler::ResultAlpha swizzle_bgrx_to_n32(
 // kBGRA
 
 static SkSwizzler::ResultAlpha swizzle_bgra_to_n32_unpremul(
-        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int dstWidth,
-        int deltaSrc, int offset, const SkPMColor ctable[]) {
+        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int width,
+        int bytesPerPixel, const SkPMColor ctable[]) {
 
-    src += offset;
     SkPMColor* SK_RESTRICT dst = (SkPMColor*)dstRow;
     INIT_RESULT_ALPHA;
-    for (int x = 0; x < dstWidth; x++) {
+    for (int x = 0; x < width; x++) {
         uint8_t alpha = src[3];
         UPDATE_RESULT_ALPHA(alpha);
         dst[x] = SkPackARGB32NoCheck(alpha, src[2], src[1], src[0]);
-        src += deltaSrc;
+        src += bytesPerPixel;
     }
     return COMPUTE_RESULT_ALPHA;
 }
 
 static SkSwizzler::ResultAlpha swizzle_bgra_to_n32_premul(
-        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int dstWidth,
-        int deltaSrc, int offset, const SkPMColor ctable[]) {
+        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int width,
+        int bytesPerPixel, const SkPMColor ctable[]) {
 
-    src += offset;
     SkPMColor* SK_RESTRICT dst = (SkPMColor*)dstRow;
     INIT_RESULT_ALPHA;
-    for (int x = 0; x < dstWidth; x++) {
+    for (int x = 0; x < width; x++) {
         uint8_t alpha = src[3];
         UPDATE_RESULT_ALPHA(alpha);
         dst[x] = SkPreMultiplyARGB(alpha, src[2], src[1], src[0]);
-        src += deltaSrc;
+        src += bytesPerPixel;
     }
     return COMPUTE_RESULT_ALPHA;
 }
 
 // kRGBX
 static SkSwizzler::ResultAlpha swizzle_rgbx_to_n32(
-        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int dstWidth,
-        int deltaSrc, int offset, const SkPMColor ctable[]) {
+        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int width,
+        int bytesPerPixel, const SkPMColor ctable[]) {
 
-    src += offset;
     SkPMColor* SK_RESTRICT dst = (SkPMColor*)dstRow;
-    for (int x = 0; x < dstWidth; x++) {
+    for (int x = 0; x < width; x++) {
         dst[x] = SkPackARGB32(0xFF, src[0], src[1], src[2]);
-        src += deltaSrc;
+        src += bytesPerPixel;
     }
     return SkSwizzler::kOpaque_ResultAlpha;
 }
 
 static SkSwizzler::ResultAlpha swizzle_rgbx_to_565(
-       void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int dstWidth,
-       int bytesPerPixel, int offset, const SkPMColor ctable[]) {
+       void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int width,
+       int bytesPerPixel, const SkPMColor ctable[]) {
     // FIXME: Support dithering?
-    src += offset;
     uint16_t* SK_RESTRICT dst = (uint16_t*)dstRow;
-    for (int x = 0; x < dstWidth; x++) {
+    for (int x = 0; x < width; x++) {
         dst[x] = SkPack888ToRGB16(src[0], src[1], src[2]);
         src += bytesPerPixel;
     }
@@ -370,51 +331,48 @@ static SkSwizzler::ResultAlpha swizzle_rgbx_to_565(
 
 // kRGBA
 static SkSwizzler::ResultAlpha swizzle_rgba_to_n32_premul(
-        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int dstWidth,
-        int deltaSrc, int offset, const SkPMColor ctable[]) {
+        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int width,
+        int bytesPerPixel, const SkPMColor ctable[]) {
 
-    src += offset;
     SkPMColor* SK_RESTRICT dst = (SkPMColor*)dstRow;
     INIT_RESULT_ALPHA;
-    for (int x = 0; x < dstWidth; x++) {
+    for (int x = 0; x < width; x++) {
         unsigned alpha = src[3];
         UPDATE_RESULT_ALPHA(alpha);
         dst[x] = SkPreMultiplyARGB(alpha, src[0], src[1], src[2]);
-        src += deltaSrc;
+        src += bytesPerPixel;
     }
     return COMPUTE_RESULT_ALPHA;
 }
 
 static SkSwizzler::ResultAlpha swizzle_rgba_to_n32_unpremul(
-        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int dstWidth,
-        int deltaSrc, int offset, const SkPMColor ctable[]) {
+        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int width,
+        int bytesPerPixel, const SkPMColor ctable[]) {
 
-    src += offset;
     uint32_t* SK_RESTRICT dst = reinterpret_cast<uint32_t*>(dstRow);
     INIT_RESULT_ALPHA;
-    for (int x = 0; x < dstWidth; x++) {
+    for (int x = 0; x < width; x++) {
         unsigned alpha = src[3];
         UPDATE_RESULT_ALPHA(alpha);
         dst[x] = SkPackARGB32NoCheck(alpha, src[0], src[1], src[2]);
-        src += deltaSrc;
+        src += bytesPerPixel;
     }
     return COMPUTE_RESULT_ALPHA;
 }
 
 static SkSwizzler::ResultAlpha swizzle_rgba_to_n32_premul_skipZ(
-        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int dstWidth,
-        int deltaSrc, int offset, const SkPMColor ctable[]) {
+        void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int width,
+        int bytesPerPixel, const SkPMColor ctable[]) {
 
-    src += offset;
     SkPMColor* SK_RESTRICT dst = (SkPMColor*)dstRow;
     INIT_RESULT_ALPHA;
-    for (int x = 0; x < dstWidth; x++) {
+    for (int x = 0; x < width; x++) {
         unsigned alpha = src[3];
         UPDATE_RESULT_ALPHA(alpha);
         if (0 != alpha) {
             dst[x] = SkPreMultiplyARGB(alpha, src[0], src[1], src[2]);
         }
-        src += deltaSrc;
+        src += bytesPerPixel;
     }
     return COMPUTE_RESULT_ALPHA;
 }
@@ -427,12 +385,11 @@ static SkSwizzler::ResultAlpha swizzle_rgba_to_n32_premul_skipZ(
     decide whether to switch to unpremul default.
 static bool swizzle_rgba_to_n32_unpremul_skipZ(void* SK_RESTRICT dstRow,
                                                const uint8_t* SK_RESTRICT src,
-                                               int dstWidth, int bitsPerPixel, int offset,
+                                               int width, int bitsPerPixel,
                                                const SkPMColor[]) {
-    src += offset;
     SkPMColor* SK_RESTRICT dst = (SkPMColor*)dstRow;
     unsigned alphaMask = 0xFF;
-    for (int x = 0; x < dstWidth; x++) {
+    for (int x = 0; x < width; x++) {
         unsigned alpha = src[3];
         // NOTE: We cheat here. The caller requested unpremul and skip zeroes. It's possible
         // the color components are not zero, but we skip them anyway, meaning they'll remain
@@ -449,10 +406,9 @@ static bool swizzle_rgba_to_n32_unpremul_skipZ(void* SK_RESTRICT dstRow,
 
 SkSwizzler* SkSwizzler::CreateSwizzler(SkSwizzler::SrcConfig sc,
                                        const SkPMColor* ctable,
-                                       const SkImageInfo& dstInfo, 
-                                       SkCodec::ZeroInitialized zeroInit, 
-                                       const SkImageInfo& srcInfo) {
-    if (dstInfo.colorType() == kUnknown_SkColorType || kUnknown == sc) {
+                                       const SkImageInfo& info,
+                                       SkCodec::ZeroInitialized zeroInit) {
+    if (info.colorType() == kUnknown_SkColorType || kUnknown == sc) {
         return NULL;
     }
     if ((kIndex == sc || kIndex4 == sc || kIndex2 == sc || kIndex1 == sc)
@@ -460,10 +416,9 @@ SkSwizzler* SkSwizzler::CreateSwizzler(SkSwizzler::SrcConfig sc,
         return NULL;
     }
     RowProc proc = NULL;
-
     switch (sc) {
         case kBit:
-            switch (dstInfo.colorType()) {
+            switch (info.colorType()) {
                 case kN32_SkColorType:
                     proc = &swizzle_bit_to_n32;
                     break;
@@ -480,7 +435,7 @@ SkSwizzler* SkSwizzler::CreateSwizzler(SkSwizzler::SrcConfig sc,
         case kIndex1:
         case kIndex2:
         case kIndex4:
-            switch (dstInfo.colorType()) {
+            switch (info.colorType()) {
                 case kN32_SkColorType:
                     proc = &swizzle_small_index_to_n32;
                     break;
@@ -492,7 +447,7 @@ SkSwizzler* SkSwizzler::CreateSwizzler(SkSwizzler::SrcConfig sc,
             }
             break;
         case kIndex:
-            switch (dstInfo.colorType()) {
+            switch (info.colorType()) {
                 case kN32_SkColorType:
                     // We assume the color premultiplied ctable (or not) as desired.
                     if (SkCodec::kYes_ZeroInitialized == zeroInit) {
@@ -514,7 +469,7 @@ SkSwizzler* SkSwizzler::CreateSwizzler(SkSwizzler::SrcConfig sc,
             }
             break;
         case kGray:
-            switch (dstInfo.colorType()) {
+            switch (info.colorType()) {
                 case kN32_SkColorType:
                     proc = &swizzle_gray_to_n32;
                     break;
@@ -530,7 +485,7 @@ SkSwizzler* SkSwizzler::CreateSwizzler(SkSwizzler::SrcConfig sc,
             break;
         case kBGR:
         case kBGRX:
-            switch (dstInfo.colorType()) {
+            switch (info.colorType()) {
                 case kN32_SkColorType:
                     proc = &swizzle_bgrx_to_n32;
                     break;
@@ -539,9 +494,9 @@ SkSwizzler* SkSwizzler::CreateSwizzler(SkSwizzler::SrcConfig sc,
             }
             break;
         case kBGRA:
-            switch (dstInfo.colorType()) {
+            switch (info.colorType()) {
                 case kN32_SkColorType:
-                    switch (dstInfo.alphaType()) {
+                    switch (info.alphaType()) {
                         case kUnpremul_SkAlphaType:
                             proc = &swizzle_bgra_to_n32_unpremul;
                             break;
@@ -558,7 +513,7 @@ SkSwizzler* SkSwizzler::CreateSwizzler(SkSwizzler::SrcConfig sc,
             break;
         case kRGBX:
             // TODO: Support other swizzles.
-            switch (dstInfo.colorType()) {
+            switch (info.colorType()) {
                 case kN32_SkColorType:
                     proc = &swizzle_rgbx_to_n32;
                     break;
@@ -569,9 +524,9 @@ SkSwizzler* SkSwizzler::CreateSwizzler(SkSwizzler::SrcConfig sc,
             }
             break;
         case kRGBA:
-            switch (dstInfo.colorType()) {
+            switch (info.colorType()) {
                 case kN32_SkColorType:
-                    if (dstInfo.alphaType() == kUnpremul_SkAlphaType) {
+                    if (info.alphaType() == kUnpremul_SkAlphaType) {
                         // Respect zeroInit?
                         proc = &swizzle_rgba_to_n32_unpremul;
                     } else {
@@ -587,7 +542,7 @@ SkSwizzler* SkSwizzler::CreateSwizzler(SkSwizzler::SrcConfig sc,
             }
             break;
         case kRGB:
-            switch (dstInfo.colorType()) {
+            switch (info.colorType()) {
                 case kN32_SkColorType:
                     proc = &swizzle_rgbx_to_n32;
                     break;
@@ -595,14 +550,6 @@ SkSwizzler* SkSwizzler::CreateSwizzler(SkSwizzler::SrcConfig sc,
                     break;
             }
             break;
-        case kRGB_565:
-            switch (dstInfo.colorType()) {
-                case kRGB_565_SkColorType:
-                    proc = &sample565;
-                    break;
-                default:
-                    break;
-            }
         default:
             break;
     }
@@ -611,31 +558,22 @@ SkSwizzler* SkSwizzler::CreateSwizzler(SkSwizzler::SrcConfig sc,
     }
 
     // Store deltaSrc in bytes if it is an even multiple, otherwise use bits
-    int deltaSrc = SkIsAlign8(BitsPerPixel(sc)) ? BytesPerPixel(sc) : BitsPerPixel(sc);
-
-    // get sampleX based on srcInfo and dstInfo dimensions
-    int sampleX;
-    SkScaledCodec::ComputeSampleSize(dstInfo, srcInfo, &sampleX, NULL);
-    
-    return SkNEW_ARGS(SkSwizzler, (proc, ctable, deltaSrc, dstInfo, sampleX));
+    int deltaSrc = SkIsAlign8(BitsPerPixel(sc)) ? BytesPerPixel(sc) :
+            BitsPerPixel(sc);
+    return SkNEW_ARGS(SkSwizzler, (proc, ctable, deltaSrc, info));
 }
 
 SkSwizzler::SkSwizzler(RowProc proc, const SkPMColor* ctable,
-                       int deltaSrc, const SkImageInfo& info, int sampleX)
+                       int deltaSrc, const SkImageInfo& info)
     : fRowProc(proc)
     , fColorTable(ctable)
     , fDeltaSrc(deltaSrc)
     , fDstInfo(info)
-    , fSampleX(sampleX)
-    , fX0(sampleX == 1 ? 0 : sampleX >> 1)
-{
-    // check that fX0 is less than original width
-    SkASSERT(fX0 >= 0 && fX0 < fDstInfo.width() * fSampleX);
-}
+{}
 
 SkSwizzler::ResultAlpha SkSwizzler::swizzle(void* dst, const uint8_t* SK_RESTRICT src) {
     SkASSERT(NULL != dst && NULL != src);
-    return fRowProc(dst, src, fDstInfo.width(), fSampleX * fDeltaSrc, fX0 * fDeltaSrc, fColorTable);
+    return fRowProc(dst, src, fDstInfo.width(), fDeltaSrc, fColorTable);
 }
 
 void SkSwizzler::Fill(void* dstStartRow, const SkImageInfo& dstInfo, size_t dstRowBytes,
diff --git a/src/codec/SkSwizzler.h b/src/codec/SkSwizzler.h
index b7132ce6d5..2fab7f66b6 100644
--- a/src/codec/SkSwizzler.h
+++ b/src/codec/SkSwizzler.h
@@ -117,22 +117,16 @@ public:
     /**
      *  Create a new SkSwizzler.
      *  @param SrcConfig Description of the format of the source.
-     *  @param dstInfo describes the destination.
+     *  @param SkImageInfo dimensions() describe both the src and the dst.
+     *              Other fields describe the dst.
      *  @param ZeroInitialized Whether dst is zero-initialized. The
                                implementation may choose to skip writing zeroes
      *                         if set to kYes_ZeroInitialized.
-     *  @param srcInfo is the info of the source. Used to calculate the width samplesize.
-     *                  Width sampling is supported by the swizzler, by skipping pixels when 
-                        swizzling the row. Height sampling is not supported by the swizzler, 
-                        but is implemented in SkScaledCodec.
-                        Sampling in Y can be done by a client with a scanline decoder, 
-                        but sampling in X allows the swizzler to skip swizzling pixels and
-                        reading from and writing to memory.
      *  @return A new SkSwizzler or NULL on failure.
      */
     static SkSwizzler* CreateSwizzler(SrcConfig, const SkPMColor* ctable,
-                                      const SkImageInfo& dstInfo, SkCodec::ZeroInitialized, 
-                                      const SkImageInfo& srcInfo);
+                                      const SkImageInfo&, SkCodec::ZeroInitialized);
+
     /**
      * Fill the remainder of the destination with a single color
      *
@@ -187,16 +181,14 @@ private:
      *  Method for converting raw data to Skia pixels.
      *  @param dstRow Row in which to write the resulting pixels.
      *  @param src Row of src data, in format specified by SrcConfig
-     *  @param dstWidth Width in pixels of the destination
+     *  @param width Width in pixels
      *  @param deltaSrc if bitsPerPixel % 8 == 0, deltaSrc is bytesPerPixel
      *                  else, deltaSrc is bitsPerPixel
      *  @param ctable Colors (used for kIndex source).
-     *  @param offset The offset before the first pixel to sample.
-                        Is in bytes or bits based on what deltaSrc is in.
      */
     typedef ResultAlpha (*RowProc)(void* SK_RESTRICT dstRow,
                                    const uint8_t* SK_RESTRICT src,
-                                   int dstWidth, int deltaSrc, int offset,
+                                   int width, int deltaSrc,
                                    const SkPMColor ctable[]);
 
     const RowProc       fRowProc;
@@ -207,10 +199,9 @@ private:
                                           //     deltaSrc is bitsPerPixel
     const SkImageInfo   fDstInfo;
     int                 fCurrY;
-    const int           fX0;              // first X coord to sample
-    const int           fSampleX;         // step between X samples
 
-    SkSwizzler(RowProc proc, const SkPMColor* ctable, int deltaSrc, const SkImageInfo& info, 
-               int sampleX);
+    SkSwizzler(RowProc proc, const SkPMColor* ctable, int deltaSrc,
+               const SkImageInfo& info);
+
 };
 #endif // SkSwizzler_DEFINED