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Diffstat (limited to 'src/codec/SkJpegCodec.cpp')
-rw-r--r--src/codec/SkJpegCodec.cpp175
1 files changed, 171 insertions, 4 deletions
diff --git a/src/codec/SkJpegCodec.cpp b/src/codec/SkJpegCodec.cpp
index a342cd8b6a..e920de1956 100644
--- a/src/codec/SkJpegCodec.cpp
+++ b/src/codec/SkJpegCodec.cpp
@@ -29,6 +29,160 @@ bool SkJpegCodec::IsJpeg(const void* buffer, size_t bytesRead) {
return bytesRead >= 3 && !memcmp(buffer, jpegSig, sizeof(jpegSig));
}
+static uint32_t get_endian_int(const uint8_t* data, bool littleEndian) {
+ if (littleEndian) {
+ return (data[3] << 24) | (data[2] << 16) | (data[1] << 8) | (data[0]);
+ }
+
+ return (data[0] << 24) | (data[1] << 16) | (data[2] << 8) | (data[3]);
+}
+
+const uint32_t kExifHeaderSize = 14;
+const uint32_t kICCHeaderSize = 14;
+const uint32_t kExifMarker = JPEG_APP0 + 1;
+const uint32_t kICCMarker = JPEG_APP0 + 2;
+
+static bool is_orientation_marker(jpeg_marker_struct* marker, SkCodec::Origin* orientation) {
+ if (kExifMarker != marker->marker || marker->data_length < kExifHeaderSize) {
+ return false;
+ }
+
+ const uint8_t* data = marker->data;
+ static const uint8_t kExifSig[] { 'E', 'x', 'i', 'f', '\0' };
+ if (memcmp(data, kExifSig, sizeof(kExifSig))) {
+ return false;
+ }
+
+ bool littleEndian;
+ if (!is_valid_endian_marker(data + 6, &littleEndian)) {
+ return false;
+ }
+
+ // Get the offset from the start of the marker.
+ // Account for 'E', 'x', 'i', 'f', '\0', '<fill byte>'.
+ uint32_t offset = get_endian_int(data + 10, littleEndian);
+ offset += sizeof(kExifSig) + 1;
+
+ // Require that the marker is at least large enough to contain the number of entries.
+ if (marker->data_length < offset + 2) {
+ return false;
+ }
+ uint32_t numEntries = get_endian_short(data + offset, littleEndian);
+
+ // Tag (2 bytes), Datatype (2 bytes), Number of elements (4 bytes), Data (4 bytes)
+ const uint32_t kEntrySize = 12;
+ numEntries = SkTMin(numEntries, (marker->data_length - offset - 2) / kEntrySize);
+
+ // Advance the data to the start of the entries.
+ data += offset + 2;
+
+ const uint16_t kOriginTag = 0x112;
+ const uint16_t kOriginType = 3;
+ for (uint32_t i = 0; i < numEntries; i++, data += kEntrySize) {
+ uint16_t tag = get_endian_short(data, littleEndian);
+ uint16_t type = get_endian_short(data + 2, littleEndian);
+ uint32_t count = get_endian_int(data + 4, littleEndian);
+ if (kOriginTag == tag && kOriginType == type && 1 == count) {
+ uint16_t val = get_endian_short(data + 8, littleEndian);
+ if (0 < val && val <= SkCodec::kLast_Origin) {
+ *orientation = (SkCodec::Origin) val;
+ return true;
+ }
+ }
+ }
+
+ return false;
+}
+
+static SkCodec::Origin get_exif_orientation(jpeg_decompress_struct* dinfo) {
+ SkCodec::Origin orientation;
+ for (jpeg_marker_struct* marker = dinfo->marker_list; marker; marker = marker->next) {
+ if (is_orientation_marker(marker, &orientation)) {
+ return orientation;
+ }
+ }
+
+ return SkCodec::kDefault_Origin;
+}
+
+static bool is_icc_marker(jpeg_marker_struct* marker) {
+ if (kICCMarker != marker->marker || marker->data_length < kICCHeaderSize) {
+ return false;
+ }
+
+ static const uint8_t kICCSig[] { 'I', 'C', 'C', '_', 'P', 'R', 'O', 'F', 'I', 'L', 'E', '\0' };
+ return !memcmp(marker->data, kICCSig, sizeof(kICCSig));
+}
+
+/*
+ * ICC profiles may be stored using a sequence of multiple markers. We obtain the ICC profile
+ * in two steps:
+ * (1) Discover all ICC profile markers and verify that they are numbered properly.
+ * (2) Copy the data from each marker into a contiguous ICC profile.
+ */
+static sk_sp<SkColorSpace> get_icc_profile(jpeg_decompress_struct* dinfo) {
+ // Note that 256 will be enough storage space since each markerIndex is stored in 8-bits.
+ jpeg_marker_struct* markerSequence[256];
+ memset(markerSequence, 0, sizeof(markerSequence));
+ uint8_t numMarkers = 0;
+ size_t totalBytes = 0;
+
+ // Discover any ICC markers and verify that they are numbered properly.
+ for (jpeg_marker_struct* marker = dinfo->marker_list; marker; marker = marker->next) {
+ if (is_icc_marker(marker)) {
+ // Verify that numMarkers is valid and consistent.
+ if (0 == numMarkers) {
+ numMarkers = marker->data[13];
+ if (0 == numMarkers) {
+ SkCodecPrintf("ICC Profile Error: numMarkers must be greater than zero.\n");
+ return nullptr;
+ }
+ } else if (numMarkers != marker->data[13]) {
+ SkCodecPrintf("ICC Profile Error: numMarkers must be consistent.\n");
+ return nullptr;
+ }
+
+ // Verify that the markerIndex is valid and unique. Note that zero is not
+ // a valid index.
+ uint8_t markerIndex = marker->data[12];
+ if (markerIndex == 0 || markerIndex > numMarkers) {
+ SkCodecPrintf("ICC Profile Error: markerIndex is invalid.\n");
+ return nullptr;
+ }
+ if (markerSequence[markerIndex]) {
+ SkCodecPrintf("ICC Profile Error: Duplicate value of markerIndex.\n");
+ return nullptr;
+ }
+ markerSequence[markerIndex] = marker;
+ SkASSERT(marker->data_length >= kICCHeaderSize);
+ totalBytes += marker->data_length - kICCHeaderSize;
+ }
+ }
+
+ if (0 == totalBytes) {
+ // No non-empty ICC profile markers were found.
+ return nullptr;
+ }
+
+ // Combine the ICC marker data into a contiguous profile.
+ SkAutoMalloc iccData(totalBytes);
+ void* dst = iccData.get();
+ for (uint32_t i = 1; i <= numMarkers; i++) {
+ jpeg_marker_struct* marker = markerSequence[i];
+ if (!marker) {
+ SkCodecPrintf("ICC Profile Error: Missing marker %d of %d.\n", i, numMarkers);
+ return nullptr;
+ }
+
+ void* src = SkTAddOffset<void>(marker->data, kICCHeaderSize);
+ size_t bytes = marker->data_length - kICCHeaderSize;
+ memcpy(dst, src, bytes);
+ dst = SkTAddOffset<void>(dst, bytes);
+ }
+
+ return SkColorSpace::NewICC(iccData.get(), totalBytes);
+}
+
bool SkJpegCodec::ReadHeader(SkStream* stream, SkCodec** codecOut,
JpegDecoderMgr** decoderMgrOut) {
@@ -43,19 +197,32 @@ bool SkJpegCodec::ReadHeader(SkStream* stream, SkCodec** codecOut,
// Initialize the decompress info and the source manager
decoderMgr->init();
+ // Instruct jpeg library to save the markers that we care about. Since
+ // the orientation and color profile will not change, we can skip this
+ // step on rewinds.
+ if (codecOut) {
+ jpeg_save_markers(decoderMgr->dinfo(), kExifMarker, 0xFFFF);
+ jpeg_save_markers(decoderMgr->dinfo(), kICCMarker, 0xFFFF);
+ }
+
// Read the jpeg header
if (JPEG_HEADER_OK != jpeg_read_header(decoderMgr->dinfo(), true)) {
return decoderMgr->returnFalse("read_header");
}
- if (nullptr != codecOut) {
+ if (codecOut) {
// Recommend the color type to decode to
const SkColorType colorType = decoderMgr->getColorType();
// Create image info object and the codec
const SkImageInfo& imageInfo = SkImageInfo::Make(decoderMgr->dinfo()->image_width,
decoderMgr->dinfo()->image_height, colorType, kOpaque_SkAlphaType);
- *codecOut = new SkJpegCodec(imageInfo, stream, decoderMgr.release());
+
+ Origin orientation = get_exif_orientation(decoderMgr->dinfo());
+ sk_sp<SkColorSpace> colorSpace = get_icc_profile(decoderMgr->dinfo());
+
+ *codecOut = new SkJpegCodec(imageInfo, stream, decoderMgr.release(), colorSpace,
+ orientation);
} else {
SkASSERT(nullptr != decoderMgrOut);
*decoderMgrOut = decoderMgr.release();
@@ -76,8 +243,8 @@ SkCodec* SkJpegCodec::NewFromStream(SkStream* stream) {
}
SkJpegCodec::SkJpegCodec(const SkImageInfo& srcInfo, SkStream* stream,
- JpegDecoderMgr* decoderMgr)
- : INHERITED(srcInfo, stream)
+ JpegDecoderMgr* decoderMgr, sk_sp<SkColorSpace> colorSpace, Origin origin)
+ : INHERITED(srcInfo, stream, colorSpace, origin)
, fDecoderMgr(decoderMgr)
, fReadyState(decoderMgr->dinfo()->global_state)
, fSwizzlerSubset(SkIRect::MakeEmpty())