diff options
Diffstat (limited to 'src/codec/SkJpegCodec.cpp')
-rw-r--r-- | src/codec/SkJpegCodec.cpp | 315 |
1 files changed, 167 insertions, 148 deletions
diff --git a/src/codec/SkJpegCodec.cpp b/src/codec/SkJpegCodec.cpp index 5e24b17848..9c9bd77c13 100644 --- a/src/codec/SkJpegCodec.cpp +++ b/src/codec/SkJpegCodec.cpp @@ -15,23 +15,53 @@ #include "SkTemplates.h" #include "SkTypes.h" -// stdio is needed for libjpeg-turbo +// stdio is needed for jpeglib #include <stdio.h> extern "C" { - #include "jpeglibmangler.h" #include "jerror.h" + #include "jmorecfg.h" #include "jpegint.h" #include "jpeglib.h" } +// ANDROID_RGB +// If this is defined in the jpeg headers it indicates that jpeg offers +// support for two additional formats: JCS_RGBA_8888 and JCS_RGB_565. + /* - * Convert a row of CMYK samples to RGBA in place. + * Get the source configuarion for the swizzler + */ +SkSwizzler::SrcConfig get_src_config(const jpeg_decompress_struct& dinfo) { + if (JCS_CMYK == dinfo.out_color_space) { + // We will need to perform a manual conversion + return SkSwizzler::kRGBX; + } + if (3 == dinfo.out_color_components && JCS_RGB == dinfo.out_color_space) { + return SkSwizzler::kRGB; + } +#ifdef ANDROID_RGB + if (JCS_RGBA_8888 == dinfo.out_color_space) { + return SkSwizzler::kRGBX; + } + + if (JCS_RGB_565 == dinfo.out_color_space) { + return SkSwizzler::kRGB_565; + } +#endif + if (1 == dinfo.out_color_components && JCS_GRAYSCALE == dinfo.out_color_space) { + return SkSwizzler::kGray; + } + return SkSwizzler::kUnknown; +} + +/* + * Convert a row of CMYK samples to RGBX in place. * Note that this method moves the row pointer. * @param width the number of pixels in the row that is being converted * CMYK is stored as four bytes per pixel */ -static void convert_CMYK_to_RGBA(uint8_t* row, uint32_t width) { +static void convert_CMYK_to_RGB(uint8_t* row, uint32_t width) { // We will implement a crude conversion from CMYK -> RGB using formulas // from easyrgb.com. // @@ -74,16 +104,9 @@ static void convert_CMYK_to_RGBA(uint8_t* row, uint32_t width) { // G = M * K / 255 // B = Y * K / 255 for (uint32_t x = 0; x < width; x++, row += 4) { -#if defined(SK_PMCOLOR_IS_RGBA) row[0] = SkMulDiv255Round(row[0], row[3]); row[1] = SkMulDiv255Round(row[1], row[3]); row[2] = SkMulDiv255Round(row[2], row[3]); -#else - uint8_t tmp = row[0]; - row[0] = SkMulDiv255Round(row[2], row[3]); - row[1] = SkMulDiv255Round(row[1], row[3]); - row[2] = SkMulDiv255Round(tmp, row[3]); -#endif row[3] = 0xFF; } } @@ -110,7 +133,7 @@ bool SkJpegCodec::ReadHeader(SkStream* stream, SkCodec** codecOut, decoderMgr->init(); // Read the jpeg header - if (JPEG_HEADER_OK != turbo_jpeg_read_header(decoderMgr->dinfo(), true)) { + if (JPEG_HEADER_OK != jpeg_read_header(decoderMgr->dinfo(), true)) { return decoderMgr->returnFalse("read_header"); } @@ -145,32 +168,24 @@ SkJpegCodec::SkJpegCodec(const SkImageInfo& srcInfo, SkStream* stream, JpegDecoderMgr* decoderMgr) : INHERITED(srcInfo, stream) , fDecoderMgr(decoderMgr) + , fSwizzler(NULL) + , fSrcRowBytes(0) {} /* * Return a valid set of output dimensions for this decoder, given an input scale */ SkISize SkJpegCodec::onGetScaledDimensions(float desiredScale) const { - // libjpeg-turbo supports scaling by 1/8, 1/4, 3/8, 1/2, 5/8, 3/4, 7/8, and 1/1, so we will - // support these as well - long num; - long denom = 8; - if (desiredScale > 0.875f) { - num = 8; - } else if (desiredScale > 0.75f) { - num = 7; - } else if (desiredScale > 0.625f) { - num = 6; - } else if (desiredScale > 0.5f) { - num = 5; + // libjpeg supports scaling by 1/1, 1/2, 1/4, and 1/8, so we will support these as well + long scale; + if (desiredScale > 0.75f) { + scale = 1; } else if (desiredScale > 0.375f) { - num = 4; - } else if (desiredScale > 0.25f) { - num = 3; - } else if (desiredScale > 0.125f) { - num = 2; + scale = 2; + } else if (desiredScale > 0.1875f) { + scale = 4; } else { - num = 1; + scale = 8; } // Set up a fake decompress struct in order to use libjpeg to calculate output dimensions @@ -180,15 +195,40 @@ SkISize SkJpegCodec::onGetScaledDimensions(float desiredScale) const { dinfo.image_height = this->getInfo().height(); dinfo.global_state = DSTATE_READY; dinfo.num_components = 0; - dinfo.scale_num = num; - dinfo.scale_denom = denom; - turbo_jpeg_calc_output_dimensions(&dinfo); + dinfo.scale_num = 1; + dinfo.scale_denom = scale; + jpeg_calc_output_dimensions(&dinfo); // Return the calculated output dimensions for the given scale return SkISize::Make(dinfo.output_width, dinfo.output_height); } /* + * Checks if the conversion between the input image and the requested output + * image has been implemented + */ +static bool conversion_possible(const SkImageInfo& dst, + const SkImageInfo& src) { + // Ensure that the profile type is unchanged + if (dst.profileType() != src.profileType()) { + return false; + } + + // Ensure that the alpha type is opaque + if (kOpaque_SkAlphaType != dst.alphaType()) { + return false; + } + + // Always allow kN32 as the color type + if (kN32_SkColorType == dst.colorType()) { + return true; + } + + // Otherwise require that the destination color type match our recommendation + return dst.colorType() == src.colorType(); +} + +/* * Handles rewinding the input stream if it is necessary */ bool SkJpegCodec::handleRewind() { @@ -213,90 +253,44 @@ bool SkJpegCodec::handleRewind() { } /* - * Checks if the conversion between the input image and the requested output - * image has been implemented - * Sets the output color space - */ -bool SkJpegCodec::setOutputColorSpace(const SkImageInfo& dst) { - const SkImageInfo& src = this->getInfo(); - - // Ensure that the profile type is unchanged - if (dst.profileType() != src.profileType()) { - return false; - } - - // Ensure that the alpha type is opaque - if (kOpaque_SkAlphaType != dst.alphaType()) { - return false; - } - - // Check if we will decode to CMYK because a conversion to RGBA is not supported - J_COLOR_SPACE colorSpace = fDecoderMgr->dinfo()->jpeg_color_space; - bool isCMYK = JCS_CMYK == colorSpace || JCS_YCCK == colorSpace; - - // Check for valid color types and set the output color space - switch (dst.colorType()) { - case kN32_SkColorType: - if (isCMYK) { - fDecoderMgr->dinfo()->out_color_space = JCS_CMYK; - } else { - // Check the byte ordering of the RGBA color space for the - // current platform -#if defined(SK_PMCOLOR_IS_RGBA) - fDecoderMgr->dinfo()->out_color_space = JCS_EXT_RGBA; -#else - fDecoderMgr->dinfo()->out_color_space = JCS_EXT_BGRA; -#endif - } - return true; - case kRGB_565_SkColorType: - if (isCMYK) { - return false; - } else { - fDecoderMgr->dinfo()->out_color_space = JCS_RGB565; - } - return true; - case kGray_8_SkColorType: - if (isCMYK) { - return false; - } else { - // We will enable decodes to gray even if the image is color because this is - // much faster than decoding to color and then converting - fDecoderMgr->dinfo()->out_color_space = JCS_GRAYSCALE; - } - return true; - default: - return false; - } -} - -/* * Checks if we can scale to the requested dimensions and scales the dimensions * if possible */ 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; - turbo_jpeg_calc_output_dimensions(fDecoderMgr->dinfo()); + // libjpeg can scale to 1/1, 1/2, 1/4, and 1/8 + SkASSERT(1 == fDecoderMgr->dinfo()->scale_num); + SkASSERT(1 == fDecoderMgr->dinfo()->scale_denom); + jpeg_calc_output_dimensions(fDecoderMgr->dinfo()); while (fDecoderMgr->dinfo()->output_width != dstWidth || fDecoderMgr->dinfo()->output_height != dstHeight) { // Return a failure if we have tried all of the possible scales - if (1 == fDecoderMgr->dinfo()->scale_num || + if (8 == fDecoderMgr->dinfo()->scale_denom || dstWidth > fDecoderMgr->dinfo()->output_width || dstHeight > fDecoderMgr->dinfo()->output_height) { return fDecoderMgr->returnFalse("could not scale to requested dimensions"); } // Try the next scale - fDecoderMgr->dinfo()->scale_num -= 1; - turbo_jpeg_calc_output_dimensions(fDecoderMgr->dinfo()); + fDecoderMgr->dinfo()->scale_denom *= 2; + jpeg_calc_output_dimensions(fDecoderMgr->dinfo()); } return true; } /* + * Create the swizzler based on the encoded format + */ +void SkJpegCodec::initializeSwizzler(const SkImageInfo& dstInfo, + void* dst, size_t dstRowBytes, + const Options& options) { + SkSwizzler::SrcConfig srcConfig = get_src_config(*fDecoderMgr->dinfo()); + fSwizzler.reset(SkSwizzler::CreateSwizzler(srcConfig, NULL, dstInfo, dst, dstRowBytes, + options.fZeroInitialized)); + fSrcRowBytes = SkSwizzler::BytesPerPixel(srcConfig) * dstInfo.width(); +} + +/* * Performs the jpeg decode */ SkCodec::Result SkJpegCodec::onGetPixels(const SkImageInfo& dstInfo, @@ -322,58 +316,79 @@ SkCodec::Result SkJpegCodec::onGetPixels(const SkImageInfo& dstInfo, return fDecoderMgr->returnFailure("setjmp", kInvalidInput); } - // Check if we can decode to the requested destination and set the output color space - if (!this->setOutputColorSpace(dstInfo)) { + // Check if we can decode to the requested destination + if (!conversion_possible(dstInfo, this->getInfo())) { return fDecoderMgr->returnFailure("conversion_possible", kInvalidConversion); } // Perform the necessary scaling if (!this->scaleToDimensions(dstInfo.width(), dstInfo.height())) { - return fDecoderMgr->returnFailure("cannot scale to requested dims", kInvalidScale); + fDecoderMgr->returnFailure("cannot scale to requested dims", kInvalidScale); } // Now, given valid output dimensions, we can start the decompress - if (!turbo_jpeg_start_decompress(dinfo)) { + if (!jpeg_start_decompress(dinfo)) { return fDecoderMgr->returnFailure("startDecompress", kInvalidInput); } - // The recommended output buffer height should always be 1 in high quality modes. - // If it's not, we want to know because it means our strategy is not optimal. - SkASSERT(1 == dinfo->rec_outbuf_height); + // Create the swizzler + this->initializeSwizzler(dstInfo, dst, dstRowBytes, options); + if (NULL == fSwizzler) { + return fDecoderMgr->returnFailure("getSwizzler", kUnimplemented); + } + + // This is usually 1, but can also be 2 or 4. + // If we wanted to always read one row at a time, we could, but we will save space and time + // by using the recommendation from libjpeg. + const uint32_t rowsPerDecode = dinfo->rec_outbuf_height; + SkASSERT(rowsPerDecode <= 4); + + // Create a buffer to contain decoded rows (libjpeg requires a 2D array) + SkASSERT(0 != fSrcRowBytes); + SkAutoTDeleteArray<uint8_t> srcBuffer(SkNEW_ARRAY(uint8_t, fSrcRowBytes * rowsPerDecode)); + JSAMPLE* srcRows[4]; + uint8_t* srcPtr = srcBuffer.get(); + for (uint8_t i = 0; i < rowsPerDecode; i++) { + srcRows[i] = (JSAMPLE*) srcPtr; + srcPtr += fSrcRowBytes; + } - // Perform the decode a single row at a time + // Ensure that we loop enough times to decode all of the rows + // libjpeg will prevent us from reading past the bottom of the image uint32_t dstHeight = dstInfo.height(); - JSAMPLE* dstRow = (JSAMPLE*) dst; - for (uint32_t y = 0; y < dstHeight; y++) { + for (uint32_t y = 0; y < dstHeight + rowsPerDecode - 1; y += rowsPerDecode) { // Read rows of the image - uint32_t rowsDecoded = turbo_jpeg_read_scanlines(dinfo, &dstRow, 1); + uint32_t rowsDecoded = jpeg_read_scanlines(dinfo, srcRows, rowsPerDecode); + + // Convert to RGB if necessary + if (JCS_CMYK == dinfo->out_color_space) { + convert_CMYK_to_RGB(srcRows[0], dstInfo.width() * rowsDecoded); + } + + // Swizzle to output destination + for (uint32_t i = 0; i < rowsDecoded; i++) { + fSwizzler->next(srcRows[i]); + } // If we cannot read enough rows, assume the input is incomplete - if (rowsDecoded != 1) { + if (rowsDecoded < rowsPerDecode && y + rowsDecoded < dstHeight) { // Fill the remainder of the image with black. This error handling // behavior is unspecified but SkCodec consistently uses black as // the fill color for opaque images. If the destination is kGray, // the low 8 bits of SK_ColorBLACK will be used. Conveniently, // these are zeros, which is the representation for black in kGray. - SkSwizzler::Fill(dstRow, dstInfo, dstRowBytes, dstHeight - y, SK_ColorBLACK, NULL); + SkSwizzler::Fill(fSwizzler->getDstRow(), dstInfo, dstRowBytes, + dstHeight - y - rowsDecoded, SK_ColorBLACK, NULL); // Prevent libjpeg from failing on incomplete decode dinfo->output_scanline = dstHeight; // Finish the decode and indicate that the input was incomplete. - turbo_jpeg_finish_decompress(dinfo); + jpeg_finish_decompress(dinfo); return fDecoderMgr->returnFailure("Incomplete image data", kIncompleteInput); } - - // Convert to RGBA if necessary - if (JCS_CMYK == dinfo->out_color_space) { - convert_CMYK_to_RGBA(dstRow, dstInfo.width()); - } - - // Move to the next row - dstRow = SkTAddOffset<JSAMPLE>(dstRow, dstRowBytes); } - turbo_jpeg_finish_decompress(dinfo); + jpeg_finish_decompress(dinfo); return kSuccess; } @@ -393,7 +408,7 @@ SkJpegCodec::~SkJpegCodec() { // We may not have decoded the entire image. Prevent libjpeg-turbo from failing on a // partial decode. fDecoderMgr->dinfo()->output_scanline = this->getInfo().height(); - turbo_jpeg_finish_decompress(fDecoderMgr->dinfo()); + jpeg_finish_decompress(fDecoderMgr->dinfo()); } } @@ -405,7 +420,10 @@ public: SkJpegScanlineDecoder(const SkImageInfo& dstInfo, SkJpegCodec* codec) : INHERITED(dstInfo) , fCodec(codec) - {} + { + fStorage.reset(fCodec->fSrcRowBytes); + fSrcRow = static_cast<uint8_t*>(fStorage.get()); + } SkImageGenerator::Result onGetScanlines(void* dst, int count, size_t rowBytes) override { // Set the jump location for libjpeg errors @@ -414,52 +432,46 @@ public: } // 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 = - turbo_jpeg_read_scanlines(fCodec->fDecoderMgr->dinfo(), &dstRow, 1); + uint32_t rowsDecoded = jpeg_read_scanlines(fCodec->fDecoderMgr->dinfo(), &fSrcRow, 1); if (rowsDecoded != 1) { - SkSwizzler::Fill( - dstRow, this->dstInfo(), rowBytes, count - y, SK_ColorBLACK, NULL); - fCodec->fDecoderMgr->dinfo()->output_scanline = this->dstInfo().height(); + SkSwizzler::Fill(dst, this->dstInfo(), rowBytes, count - y, SK_ColorBLACK, NULL); return SkImageGenerator::kIncompleteInput; } - // Convert to RGBA if necessary + // Convert to RGB if necessary if (JCS_CMYK == fCodec->fDecoderMgr->dinfo()->out_color_space) { - convert_CMYK_to_RGBA(dstRow, this->dstInfo().width()); + convert_CMYK_to_RGB(fSrcRow, dstInfo().width()); } - // Move to the next row - dstRow = SkTAddOffset<JSAMPLE>(dstRow, rowBytes); + // Swizzle to output destination + fCodec->fSwizzler->setDstRow(dst); + fCodec->fSwizzler->next(fSrcRow); + dst = SkTAddOffset<void>(dst, rowBytes); } return SkImageGenerator::kSuccess; } -#ifndef TURBO_HAS_SKIP -#define turbo_jpeg_skip_scanlines(dinfo, count) \ - 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++) { \ - turbo_jpeg_read_scanlines(dinfo, &storagePtr, 1); \ - } -#endif - SkImageGenerator::Result onSkipScanlines(int count) override { // Set the jump location for libjpeg errors if (setjmp(fCodec->fDecoderMgr->getJmpBuf())) { return fCodec->fDecoderMgr->returnFailure("setjmp", SkImageGenerator::kInvalidInput); } - turbo_jpeg_skip_scanlines(fCodec->fDecoderMgr->dinfo(), count); + // Read rows but ignore the output + for (int y = 0; y < count; y++) { + jpeg_read_scanlines(fCodec->fDecoderMgr->dinfo(), &fSrcRow, 1); + } return SkImageGenerator::kSuccess; } private: - SkJpegCodec* fCodec; // unowned + SkJpegCodec* fCodec; // unowned + SkAutoMalloc fStorage; + uint8_t* fSrcRow; // ptr into fStorage typedef SkScanlineDecoder INHERITED; }; @@ -479,24 +491,31 @@ SkScanlineDecoder* SkJpegCodec::onGetScanlineDecoder(const SkImageInfo& dstInfo, return NULL; } - // Check if we can decode to the requested destination and set the output color space - if (!this->setOutputColorSpace(dstInfo)) { + // Check if we can decode to the requested destination + if (!conversion_possible(dstInfo, this->getInfo())) { SkCodecPrintf("Cannot convert to output type\n"); return NULL; } // Perform the necessary scaling if (!this->scaleToDimensions(dstInfo.width(), dstInfo.height())) { - SkCodecPrintf("Cannot scale to output dimensions\n"); + SkCodecPrintf("Cannot scale ot output dimensions\n"); return NULL; } // Now, given valid output dimensions, we can start the decompress - if (!turbo_jpeg_start_decompress(fDecoderMgr->dinfo())) { + if (!jpeg_start_decompress(fDecoderMgr->dinfo())) { SkCodecPrintf("start decompress failed\n"); return NULL; } + // Create the swizzler + this->initializeSwizzler(dstInfo, NULL, dstInfo.minRowBytes(), options); + if (NULL == fSwizzler) { + SkCodecPrintf("Could not create swizzler\n"); + return NULL; + } + // Return the new scanline decoder return SkNEW_ARGS(SkJpegScanlineDecoder, (dstInfo, this)); } |