Index: src/images/SkImageDecoder_libjpeg.cpp |
diff --git a/src/images/SkImageDecoder_libjpeg.cpp b/src/images/SkImageDecoder_libjpeg.cpp |
index fd10bdbdf602cba14602f00476192ff23e32a312..89bfefcd45f2ae68b98a7d6030fbac7f9a7f0eef 100644 |
--- a/src/images/SkImageDecoder_libjpeg.cpp |
+++ b/src/images/SkImageDecoder_libjpeg.cpp |
@@ -6,10 +6,13 @@ |
*/ |
+#include "SkImageDecoder.h" |
#include "SkImageEncoder.h" |
#include "SkJpegUtility.h" |
#include "SkColorPriv.h" |
#include "SkDither.h" |
+#include "SkMSAN.h" |
+#include "SkScaledBitmapSampler.h" |
#include "SkStream.h" |
#include "SkTemplates.h" |
#include "SkTime.h" |
@@ -25,11 +28,729 @@ |
#include "jerror.h" |
} |
-// These enable timing code that report milliseconds for an encoding |
+// These enable timing code that report milliseconds for an encoding/decoding |
//#define TIME_ENCODE |
+//#define TIME_DECODE |
// this enables our rgb->yuv code, which is faster than libjpeg on ARM |
#define WE_CONVERT_TO_YUV |
+ |
+// If ANDROID_RGB is defined by in the jpeg headers it indicates that jpeg offers |
+// support for two additional formats (1) JCS_RGBA_8888 and (2) JCS_RGB_565. |
+ |
+#define DEFAULT_FOR_SUPPRESS_JPEG_IMAGE_DECODER_WARNINGS true |
+#define DEFAULT_FOR_SUPPRESS_JPEG_IMAGE_DECODER_ERRORS true |
+SK_CONF_DECLARE(bool, c_suppressJPEGImageDecoderWarnings, |
+ "images.jpeg.suppressDecoderWarnings", |
+ DEFAULT_FOR_SUPPRESS_JPEG_IMAGE_DECODER_WARNINGS, |
+ "Suppress most JPG warnings when calling decode functions."); |
+SK_CONF_DECLARE(bool, c_suppressJPEGImageDecoderErrors, |
+ "images.jpeg.suppressDecoderErrors", |
+ DEFAULT_FOR_SUPPRESS_JPEG_IMAGE_DECODER_ERRORS, |
+ "Suppress most JPG error messages when decode " |
+ "function fails."); |
+ |
+////////////////////////////////////////////////////////////////////////// |
+////////////////////////////////////////////////////////////////////////// |
+ |
+static void do_nothing_emit_message(jpeg_common_struct*, int) { |
+ /* do nothing */ |
+} |
+static void do_nothing_output_message(j_common_ptr) { |
+ /* do nothing */ |
+} |
+ |
+static void initialize_info(jpeg_decompress_struct* cinfo, skjpeg_source_mgr* src_mgr) { |
+ SkASSERT(cinfo != nullptr); |
+ SkASSERT(src_mgr != nullptr); |
+ jpeg_create_decompress(cinfo); |
+ cinfo->src = src_mgr; |
+ /* To suppress warnings with a SK_DEBUG binary, set the |
+ * environment variable "skia_images_jpeg_suppressDecoderWarnings" |
+ * to "true". Inside a program that links to skia: |
+ * SK_CONF_SET("images.jpeg.suppressDecoderWarnings", true); */ |
+ if (c_suppressJPEGImageDecoderWarnings) { |
+ cinfo->err->emit_message = &do_nothing_emit_message; |
+ } |
+ /* To suppress error messages with a SK_DEBUG binary, set the |
+ * environment variable "skia_images_jpeg_suppressDecoderErrors" |
+ * to "true". Inside a program that links to skia: |
+ * SK_CONF_SET("images.jpeg.suppressDecoderErrors", true); */ |
+ if (c_suppressJPEGImageDecoderErrors) { |
+ cinfo->err->output_message = &do_nothing_output_message; |
+ } |
+} |
+ |
+class SkJPEGImageDecoder : public SkImageDecoder { |
+public: |
+ |
+ Format getFormat() const override { |
+ return kJPEG_Format; |
+ } |
+ |
+protected: |
+ Result onDecode(SkStream* stream, SkBitmap* bm, Mode) override; |
+ bool onDecodeYUV8Planes(SkStream* stream, SkISize componentSizes[3], |
+ void* planes[3], size_t rowBytes[3], |
+ SkYUVColorSpace* colorSpace) override; |
+ |
+private: |
+ |
+ /** |
+ * Determine the appropriate bitmap colortype and out_color_space based on |
+ * both the preference of the caller and the jpeg_color_space on the |
+ * jpeg_decompress_struct passed in. |
+ * Must be called after jpeg_read_header. |
+ */ |
+ SkColorType getBitmapColorType(jpeg_decompress_struct*); |
+ |
+ typedef SkImageDecoder INHERITED; |
+}; |
+ |
+////////////////////////////////////////////////////////////////////////// |
+ |
+/* Automatically clean up after throwing an exception */ |
+class JPEGAutoClean { |
+public: |
+ JPEGAutoClean(): cinfo_ptr(nullptr) {} |
+ ~JPEGAutoClean() { |
+ if (cinfo_ptr) { |
+ jpeg_destroy_decompress(cinfo_ptr); |
+ } |
+ } |
+ void set(jpeg_decompress_struct* info) { |
+ cinfo_ptr = info; |
+ } |
+private: |
+ jpeg_decompress_struct* cinfo_ptr; |
+}; |
+ |
+/////////////////////////////////////////////////////////////////////////////// |
+ |
+/* If we need to better match the request, we might examine the image and |
+ output dimensions, and determine if the downsampling jpeg provided is |
+ not sufficient. If so, we can recompute a modified sampleSize value to |
+ make up the difference. |
+ |
+ To skip this additional scaling, just set sampleSize = 1; below. |
+ */ |
+static int recompute_sampleSize(int sampleSize, |
+ const jpeg_decompress_struct& cinfo) { |
+ return sampleSize * cinfo.output_width / cinfo.image_width; |
+} |
+ |
+static bool valid_output_dimensions(const jpeg_decompress_struct& cinfo) { |
+ /* These are initialized to 0, so if they have non-zero values, we assume |
+ they are "valid" (i.e. have been computed by libjpeg) |
+ */ |
+ return 0 != cinfo.output_width && 0 != cinfo.output_height; |
+} |
+ |
+static bool skip_src_rows(jpeg_decompress_struct* cinfo, void* buffer, int count) { |
+ for (int i = 0; i < count; i++) { |
+ JSAMPLE* rowptr = (JSAMPLE*)buffer; |
+ int row_count = jpeg_read_scanlines(cinfo, &rowptr, 1); |
+ if (1 != row_count) { |
+ return false; |
+ } |
+ } |
+ return true; |
+} |
+ |
+/////////////////////////////////////////////////////////////////////////////// |
+ |
+// This guy exists just to aid in debugging, as it allows debuggers to just |
+// set a break-point in one place to see all error exists. |
+static void print_jpeg_decoder_errors(const jpeg_decompress_struct& cinfo, |
+ int width, int height, const char caller[]) { |
+ if (!(c_suppressJPEGImageDecoderErrors)) { |
+ char buffer[JMSG_LENGTH_MAX]; |
+ cinfo.err->format_message((const j_common_ptr)&cinfo, buffer); |
+ SkDebugf("libjpeg error %d <%s> from %s [%d %d]\n", |
+ cinfo.err->msg_code, buffer, caller, width, height); |
+ } |
+} |
+ |
+static bool return_false(const jpeg_decompress_struct& cinfo, |
+ const char caller[]) { |
+ print_jpeg_decoder_errors(cinfo, 0, 0, caller); |
+ return false; |
+} |
+ |
+static SkImageDecoder::Result return_failure(const jpeg_decompress_struct& cinfo, |
+ const SkBitmap& bm, const char caller[]) { |
+ print_jpeg_decoder_errors(cinfo, bm.width(), bm.height(), caller); |
+ return SkImageDecoder::kFailure; |
+} |
+ |
+/////////////////////////////////////////////////////////////////////////////// |
+ |
+// Convert a scanline of CMYK samples to RGBX in place. Note that this |
+// method moves the "scanline" pointer in its processing |
+static void convert_CMYK_to_RGB(uint8_t* scanline, unsigned int width) { |
+ // At this point we've received CMYK pixels from libjpeg. We |
+ // perform a crude conversion to RGB (based on the formulae |
+ // from easyrgb.com): |
+ // CMYK -> CMY |
+ // C = ( C * (1 - K) + K ) // for each CMY component |
+ // CMY -> RGB |
+ // R = ( 1 - C ) * 255 // for each RGB component |
+ // Unfortunately we are seeing inverted CMYK so all the original terms |
+ // are 1-. This yields: |
+ // CMYK -> CMY |
+ // C = ( (1-C) * (1 - (1-K) + (1-K) ) -> C = 1 - C*K |
+ // The conversion from CMY->RGB remains the same |
+ for (unsigned int x = 0; x < width; ++x, scanline += 4) { |
+ scanline[0] = SkMulDiv255Round(scanline[0], scanline[3]); |
+ scanline[1] = SkMulDiv255Round(scanline[1], scanline[3]); |
+ scanline[2] = SkMulDiv255Round(scanline[2], scanline[3]); |
+ scanline[3] = 255; |
+ } |
+} |
+ |
+/** |
+ * Common code for setting the error manager. |
+ */ |
+static void set_error_mgr(jpeg_decompress_struct* cinfo, skjpeg_error_mgr* errorManager) { |
+ SkASSERT(cinfo != nullptr); |
+ SkASSERT(errorManager != nullptr); |
+ cinfo->err = jpeg_std_error(errorManager); |
+ errorManager->error_exit = skjpeg_error_exit; |
+} |
+ |
+/** |
+ * Common code for setting the dct method. |
+ */ |
+static void set_dct_method(const SkImageDecoder& decoder, jpeg_decompress_struct* cinfo) { |
+ SkASSERT(cinfo != nullptr); |
+ cinfo->dct_method = JDCT_ISLOW; |
+} |
+ |
+SkColorType SkJPEGImageDecoder::getBitmapColorType(jpeg_decompress_struct* cinfo) { |
+ SkASSERT(cinfo != nullptr); |
+ |
+ SrcDepth srcDepth = k32Bit_SrcDepth; |
+ if (JCS_GRAYSCALE == cinfo->jpeg_color_space) { |
+ srcDepth = k8BitGray_SrcDepth; |
+ } |
+ |
+ SkColorType colorType = this->getPrefColorType(srcDepth, /*hasAlpha*/ false); |
+ switch (colorType) { |
+ case kAlpha_8_SkColorType: |
+ // Only respect A8 colortype if the original is grayscale, |
+ // in which case we will treat the grayscale as alpha |
+ // values. |
+ if (cinfo->jpeg_color_space != JCS_GRAYSCALE) { |
+ colorType = kN32_SkColorType; |
+ } |
+ break; |
+ case kN32_SkColorType: |
+ // Fall through. |
+ case kARGB_4444_SkColorType: |
+ // Fall through. |
+ case kRGB_565_SkColorType: |
+ // These are acceptable destination colortypes. |
+ break; |
+ default: |
+ // Force all other colortypes to 8888. |
+ colorType = kN32_SkColorType; |
+ break; |
+ } |
+ |
+ switch (cinfo->jpeg_color_space) { |
+ case JCS_CMYK: |
+ // Fall through. |
+ case JCS_YCCK: |
+ // libjpeg cannot convert from CMYK or YCCK to RGB - here we set up |
+ // so libjpeg will give us CMYK samples back and we will later |
+ // manually convert them to RGB |
+ cinfo->out_color_space = JCS_CMYK; |
+ break; |
+ case JCS_GRAYSCALE: |
+ if (kAlpha_8_SkColorType == colorType) { |
+ cinfo->out_color_space = JCS_GRAYSCALE; |
+ break; |
+ } |
+ // The data is JCS_GRAYSCALE, but the caller wants some sort of RGB |
+ // colortype. Fall through to set to the default. |
+ default: |
+ cinfo->out_color_space = JCS_RGB; |
+ break; |
+ } |
+ return colorType; |
+} |
+ |
+/** |
+ * Based on the colortype and dither mode, adjust out_color_space and |
+ * dither_mode of cinfo. Only does work in ANDROID_RGB |
+ */ |
+static void adjust_out_color_space_and_dither(jpeg_decompress_struct* cinfo, |
+ SkColorType colorType, |
+ const SkImageDecoder& decoder) { |
+ SkASSERT(cinfo != nullptr); |
+#ifdef ANDROID_RGB |
+ cinfo->dither_mode = JDITHER_NONE; |
+ if (JCS_CMYK == cinfo->out_color_space) { |
+ return; |
+ } |
+ switch (colorType) { |
+ case kN32_SkColorType: |
+ cinfo->out_color_space = JCS_RGBA_8888; |
+ break; |
+ case kRGB_565_SkColorType: |
+ cinfo->out_color_space = JCS_RGB_565; |
+ if (decoder.getDitherImage()) { |
+ cinfo->dither_mode = JDITHER_ORDERED; |
+ } |
+ break; |
+ default: |
+ break; |
+ } |
+#endif |
+} |
+ |
+/** |
+ Sets all pixels in given bitmap to SK_ColorWHITE for all rows >= y. |
+ Used when decoding fails partway through reading scanlines to fill |
+ remaining lines. */ |
+static void fill_below_level(int y, SkBitmap* bitmap) { |
+ SkIRect rect = SkIRect::MakeLTRB(0, y, bitmap->width(), bitmap->height()); |
+ SkCanvas canvas(*bitmap); |
+ canvas.clipRect(SkRect::Make(rect)); |
+ canvas.drawColor(SK_ColorWHITE); |
+} |
+ |
+/** |
+ * Get the config and bytes per pixel of the source data. Return |
+ * whether the data is supported. |
+ */ |
+static bool get_src_config(const jpeg_decompress_struct& cinfo, |
+ SkScaledBitmapSampler::SrcConfig* sc, |
+ int* srcBytesPerPixel) { |
+ SkASSERT(sc != nullptr && srcBytesPerPixel != nullptr); |
+ if (JCS_CMYK == cinfo.out_color_space) { |
+ // In this case we will manually convert the CMYK values to RGB |
+ *sc = SkScaledBitmapSampler::kRGBX; |
+ // The CMYK work-around relies on 4 components per pixel here |
+ *srcBytesPerPixel = 4; |
+ } else if (3 == cinfo.out_color_components && JCS_RGB == cinfo.out_color_space) { |
+ *sc = SkScaledBitmapSampler::kRGB; |
+ *srcBytesPerPixel = 3; |
+#ifdef ANDROID_RGB |
+ } else if (JCS_RGBA_8888 == cinfo.out_color_space) { |
+ *sc = SkScaledBitmapSampler::kRGBX; |
+ *srcBytesPerPixel = 4; |
+ } else if (JCS_RGB_565 == cinfo.out_color_space) { |
+ *sc = SkScaledBitmapSampler::kRGB_565; |
+ *srcBytesPerPixel = 2; |
+#endif |
+ } else if (1 == cinfo.out_color_components && |
+ JCS_GRAYSCALE == cinfo.out_color_space) { |
+ *sc = SkScaledBitmapSampler::kGray; |
+ *srcBytesPerPixel = 1; |
+ } else { |
+ return false; |
+ } |
+ return true; |
+} |
+ |
+SkImageDecoder::Result SkJPEGImageDecoder::onDecode(SkStream* stream, SkBitmap* bm, Mode mode) { |
+#ifdef TIME_DECODE |
+ SkAutoTime atm("JPEG Decode"); |
+#endif |
+ |
+ JPEGAutoClean autoClean; |
+ |
+ jpeg_decompress_struct cinfo; |
+ skjpeg_source_mgr srcManager(stream, this); |
+ |
+ skjpeg_error_mgr errorManager; |
+ set_error_mgr(&cinfo, &errorManager); |
+ |
+ // All objects need to be instantiated before this setjmp call so that |
+ // they will be cleaned up properly if an error occurs. |
+ if (setjmp(errorManager.fJmpBuf)) { |
+ return return_failure(cinfo, *bm, "setjmp"); |
+ } |
+ |
+ initialize_info(&cinfo, &srcManager); |
+ autoClean.set(&cinfo); |
+ |
+ int status = jpeg_read_header(&cinfo, true); |
+ if (status != JPEG_HEADER_OK) { |
+ return return_failure(cinfo, *bm, "read_header"); |
+ } |
+ |
+ /* Try to fulfill the requested sampleSize. Since jpeg can do it (when it |
+ can) much faster that we, just use their num/denom api to approximate |
+ the size. |
+ */ |
+ int sampleSize = this->getSampleSize(); |
+ |
+ set_dct_method(*this, &cinfo); |
+ |
+ SkASSERT(1 == cinfo.scale_num); |
+ cinfo.scale_denom = sampleSize; |
+ |
+ const SkColorType colorType = this->getBitmapColorType(&cinfo); |
+ const SkAlphaType alphaType = kAlpha_8_SkColorType == colorType ? |
+ kPremul_SkAlphaType : kOpaque_SkAlphaType; |
+ |
+ adjust_out_color_space_and_dither(&cinfo, colorType, *this); |
+ |
+ if (1 == sampleSize && SkImageDecoder::kDecodeBounds_Mode == mode) { |
+ // Assume an A8 bitmap is not opaque to avoid the check of each |
+ // individual pixel. It is very unlikely to be opaque, since |
+ // an opaque A8 bitmap would not be very interesting. |
+ // Otherwise, a jpeg image is opaque. |
+ bool success = bm->setInfo(SkImageInfo::Make(cinfo.image_width, cinfo.image_height, |
+ colorType, alphaType)); |
+ return success ? kSuccess : kFailure; |
+ } |
+ |
+ /* image_width and image_height are the original dimensions, available |
+ after jpeg_read_header(). To see the scaled dimensions, we have to call |
+ jpeg_start_decompress(), and then read output_width and output_height. |
+ */ |
+ if (!jpeg_start_decompress(&cinfo)) { |
+ /* If we failed here, we may still have enough information to return |
+ to the caller if they just wanted (subsampled bounds). If sampleSize |
+ was 1, then we would have already returned. Thus we just check if |
+ we're in kDecodeBounds_Mode, and that we have valid output sizes. |
+ |
+ One reason to fail here is that we have insufficient stream data |
+ to complete the setup. However, output dimensions seem to get |
+ computed very early, which is why this special check can pay off. |
+ */ |
+ if (SkImageDecoder::kDecodeBounds_Mode == mode && valid_output_dimensions(cinfo)) { |
+ SkScaledBitmapSampler smpl(cinfo.output_width, cinfo.output_height, |
+ recompute_sampleSize(sampleSize, cinfo)); |
+ // Assume an A8 bitmap is not opaque to avoid the check of each |
+ // individual pixel. It is very unlikely to be opaque, since |
+ // an opaque A8 bitmap would not be very interesting. |
+ // Otherwise, a jpeg image is opaque. |
+ bool success = bm->setInfo(SkImageInfo::Make(smpl.scaledWidth(), smpl.scaledHeight(), |
+ colorType, alphaType)); |
+ return success ? kSuccess : kFailure; |
+ } else { |
+ return return_failure(cinfo, *bm, "start_decompress"); |
+ } |
+ } |
+ sampleSize = recompute_sampleSize(sampleSize, cinfo); |
+ |
+ SkScaledBitmapSampler sampler(cinfo.output_width, cinfo.output_height, sampleSize); |
+ // Assume an A8 bitmap is not opaque to avoid the check of each |
+ // individual pixel. It is very unlikely to be opaque, since |
+ // an opaque A8 bitmap would not be very interesting. |
+ // Otherwise, a jpeg image is opaque. |
+ bm->setInfo(SkImageInfo::Make(sampler.scaledWidth(), sampler.scaledHeight(), |
+ colorType, alphaType)); |
+ if (SkImageDecoder::kDecodeBounds_Mode == mode) { |
+ return kSuccess; |
+ } |
+ if (!this->allocPixelRef(bm, nullptr)) { |
+ return return_failure(cinfo, *bm, "allocPixelRef"); |
+ } |
+ |
+ SkAutoLockPixels alp(*bm); |
+ |
+#ifdef ANDROID_RGB |
+ /* short-circuit the SkScaledBitmapSampler when possible, as this gives |
+ a significant performance boost. |
+ */ |
+ if (sampleSize == 1 && |
+ ((kN32_SkColorType == colorType && cinfo.out_color_space == JCS_RGBA_8888) || |
+ (kRGB_565_SkColorType == colorType && cinfo.out_color_space == JCS_RGB_565))) |
+ { |
+ JSAMPLE* rowptr = (JSAMPLE*)bm->getPixels(); |
+ INT32 const bpr = bm->rowBytes(); |
+ |
+ while (cinfo.output_scanline < cinfo.output_height) { |
+ int row_count = jpeg_read_scanlines(&cinfo, &rowptr, 1); |
+ if (0 == row_count) { |
+ // if row_count == 0, then we didn't get a scanline, |
+ // so return early. We will return a partial image. |
+ fill_below_level(cinfo.output_scanline, bm); |
+ cinfo.output_scanline = cinfo.output_height; |
+ jpeg_finish_decompress(&cinfo); |
+ return kPartialSuccess; |
+ } |
+ if (this->shouldCancelDecode()) { |
+ return return_failure(cinfo, *bm, "shouldCancelDecode"); |
+ } |
+ rowptr += bpr; |
+ } |
+ jpeg_finish_decompress(&cinfo); |
+ return kSuccess; |
+ } |
+#endif |
+ |
+ // check for supported formats |
+ SkScaledBitmapSampler::SrcConfig sc; |
+ int srcBytesPerPixel; |
+ |
+ if (!get_src_config(cinfo, &sc, &srcBytesPerPixel)) { |
+ return return_failure(cinfo, *bm, "jpeg colorspace"); |
+ } |
+ |
+ if (!sampler.begin(bm, sc, *this)) { |
+ return return_failure(cinfo, *bm, "sampler.begin"); |
+ } |
+ |
+ SkAutoTMalloc<uint8_t> srcStorage(cinfo.output_width * srcBytesPerPixel); |
+ uint8_t* srcRow = srcStorage.get(); |
+ |
+ // Possibly skip initial rows [sampler.srcY0] |
+ if (!skip_src_rows(&cinfo, srcRow, sampler.srcY0())) { |
+ return return_failure(cinfo, *bm, "skip rows"); |
+ } |
+ |
+ // now loop through scanlines until y == bm->height() - 1 |
+ for (int y = 0;; y++) { |
+ JSAMPLE* rowptr = (JSAMPLE*)srcRow; |
+ int row_count = jpeg_read_scanlines(&cinfo, &rowptr, 1); |
+ sk_msan_mark_initialized(srcRow, srcRow + cinfo.output_width * srcBytesPerPixel, |
+ "skbug.com/4550"); |
+ if (0 == row_count) { |
+ // if row_count == 0, then we didn't get a scanline, |
+ // so return early. We will return a partial image. |
+ fill_below_level(y, bm); |
+ cinfo.output_scanline = cinfo.output_height; |
+ jpeg_finish_decompress(&cinfo); |
+ return kPartialSuccess; |
+ } |
+ if (this->shouldCancelDecode()) { |
+ return return_failure(cinfo, *bm, "shouldCancelDecode"); |
+ } |
+ |
+ if (JCS_CMYK == cinfo.out_color_space) { |
+ convert_CMYK_to_RGB(srcRow, cinfo.output_width); |
+ } |
+ |
+ |
+ sampler.next(srcRow); |
+ if (bm->height() - 1 == y) { |
+ // we're done |
+ break; |
+ } |
+ |
+ if (!skip_src_rows(&cinfo, srcRow, sampler.srcDY() - 1)) { |
+ return return_failure(cinfo, *bm, "skip rows"); |
+ } |
+ } |
+ |
+ // we formally skip the rest, so we don't get a complaint from libjpeg |
+ if (!skip_src_rows(&cinfo, srcRow, |
+ cinfo.output_height - cinfo.output_scanline)) { |
+ return return_failure(cinfo, *bm, "skip rows"); |
+ } |
+ jpeg_finish_decompress(&cinfo); |
+ |
+ return kSuccess; |
+} |
+ |
+/////////////////////////////////////////////////////////////////////////////// |
+ |
+enum SizeType { |
+ kSizeForMemoryAllocation_SizeType, |
+ kActualSize_SizeType |
+}; |
+ |
+static SkISize compute_yuv_size(const jpeg_decompress_struct& info, int component, |
+ SizeType sizeType) { |
+ if (sizeType == kSizeForMemoryAllocation_SizeType) { |
+ return SkISize::Make(info.cur_comp_info[component]->width_in_blocks * DCTSIZE, |
+ info.cur_comp_info[component]->height_in_blocks * DCTSIZE); |
+ } |
+ return SkISize::Make(info.cur_comp_info[component]->downsampled_width, |
+ info.cur_comp_info[component]->downsampled_height); |
+} |
+ |
+static bool appears_to_be_yuv(const jpeg_decompress_struct& info) { |
+ return (info.jpeg_color_space == JCS_YCbCr) |
+ && (DCTSIZE == 8) |
+ && (info.num_components == 3) |
+ && (info.comps_in_scan >= info.num_components) |
+ && (info.scale_denom <= 8) |
+ && (info.cur_comp_info[0]) |
+ && (info.cur_comp_info[1]) |
+ && (info.cur_comp_info[2]) |
+ && (info.cur_comp_info[1]->h_samp_factor == 1) |
+ && (info.cur_comp_info[1]->v_samp_factor == 1) |
+ && (info.cur_comp_info[2]->h_samp_factor == 1) |
+ && (info.cur_comp_info[2]->v_samp_factor == 1); |
+} |
+ |
+static void update_components_sizes(const jpeg_decompress_struct& cinfo, SkISize componentSizes[3], |
+ SizeType sizeType) { |
+ SkASSERT(appears_to_be_yuv(cinfo)); |
+ for (int i = 0; i < 3; ++i) { |
+ componentSizes[i] = compute_yuv_size(cinfo, i, sizeType); |
+ } |
+} |
+ |
+static bool output_raw_data(jpeg_decompress_struct& cinfo, void* planes[3], size_t rowBytes[3]) { |
+ SkASSERT(appears_to_be_yuv(cinfo)); |
+ // U size and V size have to be the same if we're calling output_raw_data() |
+ SkISize uvSize = compute_yuv_size(cinfo, 1, kSizeForMemoryAllocation_SizeType); |
+ SkASSERT(uvSize == compute_yuv_size(cinfo, 2, kSizeForMemoryAllocation_SizeType)); |
+ |
+ JSAMPARRAY bufferraw[3]; |
+ JSAMPROW bufferraw2[32]; |
+ bufferraw[0] = &bufferraw2[0]; // Y channel rows (8 or 16) |
+ bufferraw[1] = &bufferraw2[16]; // U channel rows (8) |
+ bufferraw[2] = &bufferraw2[24]; // V channel rows (8) |
+ int yWidth = cinfo.output_width; |
+ int yHeight = cinfo.output_height; |
+ int yMaxH = yHeight - 1; |
+ int v = cinfo.cur_comp_info[0]->v_samp_factor; |
+ int uvMaxH = uvSize.height() - 1; |
+ JSAMPROW outputY = static_cast<JSAMPROW>(planes[0]); |
+ JSAMPROW outputU = static_cast<JSAMPROW>(planes[1]); |
+ JSAMPROW outputV = static_cast<JSAMPROW>(planes[2]); |
+ size_t rowBytesY = rowBytes[0]; |
+ size_t rowBytesU = rowBytes[1]; |
+ size_t rowBytesV = rowBytes[2]; |
+ |
+ int yScanlinesToRead = DCTSIZE * v; |
+ SkAutoMalloc lastRowStorage(rowBytesY * 4); |
+ JSAMPROW yLastRow = (JSAMPROW)lastRowStorage.get(); |
+ JSAMPROW uLastRow = yLastRow + rowBytesY; |
+ JSAMPROW vLastRow = uLastRow + rowBytesY; |
+ JSAMPROW dummyRow = vLastRow + rowBytesY; |
+ |
+ while (cinfo.output_scanline < cinfo.output_height) { |
+ // Request 8 or 16 scanlines: returns 0 or more scanlines. |
+ bool hasYLastRow(false), hasUVLastRow(false); |
+ // Assign 8 or 16 rows of memory to read the Y channel. |
+ for (int i = 0; i < yScanlinesToRead; ++i) { |
+ int scanline = (cinfo.output_scanline + i); |
+ if (scanline < yMaxH) { |
+ bufferraw2[i] = &outputY[scanline * rowBytesY]; |
+ } else if (scanline == yMaxH) { |
+ bufferraw2[i] = yLastRow; |
+ hasYLastRow = true; |
+ } else { |
+ bufferraw2[i] = dummyRow; |
+ } |
+ } |
+ int scaledScanline = cinfo.output_scanline / v; |
+ // Assign 8 rows of memory to read the U and V channels. |
+ for (int i = 0; i < 8; ++i) { |
+ int scanline = (scaledScanline + i); |
+ if (scanline < uvMaxH) { |
+ bufferraw2[16 + i] = &outputU[scanline * rowBytesU]; |
+ bufferraw2[24 + i] = &outputV[scanline * rowBytesV]; |
+ } else if (scanline == uvMaxH) { |
+ bufferraw2[16 + i] = uLastRow; |
+ bufferraw2[24 + i] = vLastRow; |
+ hasUVLastRow = true; |
+ } else { |
+ bufferraw2[16 + i] = dummyRow; |
+ bufferraw2[24 + i] = dummyRow; |
+ } |
+ } |
+ JDIMENSION scanlinesRead = jpeg_read_raw_data(&cinfo, bufferraw, yScanlinesToRead); |
+ |
+ if (scanlinesRead == 0) { |
+ return false; |
+ } |
+ |
+ if (hasYLastRow) { |
+ memcpy(&outputY[yMaxH * rowBytesY], yLastRow, yWidth); |
+ } |
+ if (hasUVLastRow) { |
+ memcpy(&outputU[uvMaxH * rowBytesU], uLastRow, uvSize.width()); |
+ memcpy(&outputV[uvMaxH * rowBytesV], vLastRow, uvSize.width()); |
+ } |
+ } |
+ |
+ cinfo.output_scanline = SkMin32(cinfo.output_scanline, cinfo.output_height); |
+ |
+ return true; |
+} |
+ |
+bool SkJPEGImageDecoder::onDecodeYUV8Planes(SkStream* stream, SkISize componentSizes[3], |
+ void* planes[3], size_t rowBytes[3], |
+ SkYUVColorSpace* colorSpace) { |
+#ifdef TIME_DECODE |
+ SkAutoTime atm("JPEG YUV8 Decode"); |
+#endif |
+ if (this->getSampleSize() != 1) { |
+ return false; // Resizing not supported |
+ } |
+ |
+ JPEGAutoClean autoClean; |
+ |
+ jpeg_decompress_struct cinfo; |
+ skjpeg_source_mgr srcManager(stream, this); |
+ |
+ skjpeg_error_mgr errorManager; |
+ set_error_mgr(&cinfo, &errorManager); |
+ |
+ // All objects need to be instantiated before this setjmp call so that |
+ // they will be cleaned up properly if an error occurs. |
+ if (setjmp(errorManager.fJmpBuf)) { |
+ return return_false(cinfo, "setjmp YUV8"); |
+ } |
+ |
+ initialize_info(&cinfo, &srcManager); |
+ autoClean.set(&cinfo); |
+ |
+ int status = jpeg_read_header(&cinfo, true); |
+ if (status != JPEG_HEADER_OK) { |
+ return return_false(cinfo, "read_header YUV8"); |
+ } |
+ |
+ if (!appears_to_be_yuv(cinfo)) { |
+ // It's not an error to not be encoded in YUV, so no need to use return_false() |
+ return false; |
+ } |
+ |
+ cinfo.out_color_space = JCS_YCbCr; |
+ cinfo.raw_data_out = TRUE; |
+ |
+ if (!planes || !planes[0] || !rowBytes || !rowBytes[0]) { // Compute size only |
+ update_components_sizes(cinfo, componentSizes, kSizeForMemoryAllocation_SizeType); |
+ return true; |
+ } |
+ |
+ set_dct_method(*this, &cinfo); |
+ |
+ SkASSERT(1 == cinfo.scale_num); |
+ cinfo.scale_denom = 1; |
+ |
+#ifdef ANDROID_RGB |
+ cinfo.dither_mode = JDITHER_NONE; |
+#endif |
+ |
+ /* image_width and image_height are the original dimensions, available |
+ after jpeg_read_header(). To see the scaled dimensions, we have to call |
+ jpeg_start_decompress(), and then read output_width and output_height. |
+ */ |
+ if (!jpeg_start_decompress(&cinfo)) { |
+ return return_false(cinfo, "start_decompress YUV8"); |
+ } |
+ |
+ // Seems like jpeg_start_decompress is updating our opinion of whether cinfo represents YUV. |
+ // Again, not really an error. |
+ if (!appears_to_be_yuv(cinfo)) { |
+ return false; |
+ } |
+ |
+ if (!output_raw_data(cinfo, planes, rowBytes)) { |
+ return return_false(cinfo, "output_raw_data"); |
+ } |
+ |
+ update_components_sizes(cinfo, componentSizes, kActualSize_SizeType); |
+ jpeg_finish_decompress(&cinfo); |
+ |
+ if (nullptr != colorSpace) { |
+ *colorSpace = kJPEG_SkYUVColorSpace; |
+ } |
+ |
+ return true; |
+} |
/////////////////////////////////////////////////////////////////////////////// |
@@ -272,11 +993,45 @@ |
}; |
/////////////////////////////////////////////////////////////////////////////// |
+DEFINE_DECODER_CREATOR(JPEGImageDecoder); |
DEFINE_ENCODER_CREATOR(JPEGImageEncoder); |
/////////////////////////////////////////////////////////////////////////////// |
+static bool is_jpeg(SkStreamRewindable* stream) { |
+ static const unsigned char gHeader[] = { 0xFF, 0xD8, 0xFF }; |
+ static const size_t HEADER_SIZE = sizeof(gHeader); |
+ |
+ char buffer[HEADER_SIZE]; |
+ size_t len = stream->read(buffer, HEADER_SIZE); |
+ |
+ if (len != HEADER_SIZE) { |
+ return false; // can't read enough |
+ } |
+ if (memcmp(buffer, gHeader, HEADER_SIZE)) { |
+ return false; |
+ } |
+ return true; |
+} |
+ |
+ |
+static SkImageDecoder* sk_libjpeg_dfactory(SkStreamRewindable* stream) { |
+ if (is_jpeg(stream)) { |
+ return new SkJPEGImageDecoder; |
+ } |
+ return nullptr; |
+} |
+ |
+static SkImageDecoder::Format get_format_jpeg(SkStreamRewindable* stream) { |
+ if (is_jpeg(stream)) { |
+ return SkImageDecoder::kJPEG_Format; |
+ } |
+ return SkImageDecoder::kUnknown_Format; |
+} |
+ |
static SkImageEncoder* sk_libjpeg_efactory(SkImageEncoder::Type t) { |
return (SkImageEncoder::kJPEG_Type == t) ? new SkJPEGImageEncoder : nullptr; |
} |
+static SkImageDecoder_DecodeReg gDReg(sk_libjpeg_dfactory); |
+static SkImageDecoder_FormatReg gFormatReg(get_format_jpeg); |
static SkImageEncoder_EncodeReg gEReg(sk_libjpeg_efactory); |