Support RGBA/BGRA swizzles using SkEncodedInfo

src/codec/SkJpegCodec.cpp

 /*
  * 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 "SkCodec.h"
 #include "SkMSAN.h"
 #include "SkJpegCodec.h"
@@ skipping 338 matching lines @@
         SkCodecPrintf("Warning: an opaque image should be decoded as opaque "
                       "- it is being decoded as non-opaque, which will draw slower\n");
     }
 
     // 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:
+        case kRGBA_8888_SkColorType:
             if (isCMYK) {
                 fDecoderMgr->dinfo()->out_color_space = JCS_CMYK;
             } else {
 #ifdef LIBJPEG_TURBO_VERSION
-            // Check the byte ordering of the RGBA color space for the
-            // current platform
-    #ifdef SK_PMCOLOR_IS_RGBA
             fDecoderMgr->dinfo()->out_color_space = JCS_EXT_RGBA;
-    #else
-            fDecoderMgr->dinfo()->out_color_space = JCS_EXT_BGRA;
-    #endif
 #else
             fDecoderMgr->dinfo()->out_color_space = JCS_RGB;
 #endif
+            }
+            return true;
+        case kBGRA_8888_SkColorType:
+            if (isCMYK) {
+                fDecoderMgr->dinfo()->out_color_space = JCS_CMYK;
+            } else {
+#ifdef LIBJPEG_TURBO_VERSION
+            fDecoderMgr->dinfo()->out_color_space = JCS_EXT_BGRA;
+#else
+            fDecoderMgr->dinfo()->out_color_space = JCS_RGB;
+#endif
             }
             return true;
         case kRGB_565_SkColorType:
             if (isCMYK) {
                 fDecoderMgr->dinfo()->out_color_space = JCS_CMYK;
             } else {
 #ifdef TURBO_HAS_565
                 fDecoderMgr->dinfo()->dither_mode = JDITHER_NONE;
                 fDecoderMgr->dinfo()->out_color_space = JCS_RGB565;
 #else
@@ skipping 125 matching lines @@
             dst = SkTAddOffset<JSAMPLE>(dst, dstRowBytes);
         } else {
             dstRow = SkTAddOffset<JSAMPLE>(dstRow, dstRowBytes);
         }
     }
 
     return kSuccess;
 }
 
 void SkJpegCodec::initializeSwizzler(const SkImageInfo& dstInfo, const Options& options) {
-    SkSwizzler::SrcConfig srcConfig = SkSwizzler::kUnknown;
-    if (JCS_CMYK == fDecoderMgr->dinfo()->out_color_space) {
-        srcConfig = SkSwizzler::kCMYK;
-    } else {
-        // If the out_color_space is not CMYK, the only reason we would need a swizzler is
-        // for sampling and/or subsetting.
-        switch (dstInfo.colorType()) {
-            case kGray_8_SkColorType:
-                srcConfig = SkSwizzler::kNoOp8;
-                break;
-            case kN32_SkColorType:
-                srcConfig = SkSwizzler::kNoOp32;
-                break;
-            case kRGB_565_SkColorType:
-                srcConfig = SkSwizzler::kNoOp16;
-                break;
-            default:
-                // This function should only be called if the colorType is supported by jpeg
-                SkASSERT(false);
-        }
-    }
-
-    if (JCS_RGB == fDecoderMgr->dinfo()->out_color_space) {
-        srcConfig = SkSwizzler::kRGB;
+    // libjpeg-turbo may have already performed color conversion.  In this
+    // case, we must indicate to the swizzler the appropriate encoded format.
+    SkEncodedInfo encodedInfo;
+    switch (fDecoderMgr->dinfo()->out_color_space) {
+        case JCS_GRAYSCALE:
+            encodedInfo = this->getEncodedInfo().makeColor(SkEncodedInfo::kGray_Color);
+            break;
+        case JCS_RGB:
+            encodedInfo = this->getEncodedInfo().makeColor(SkEncodedInfo::kRGB_Color);
+            break;
+#ifdef LIBJPEG_TURBO_VERSION
+        case JCS_EXT_RGBA:
+            encodedInfo = this->getEncodedInfo().makeColor(SkEncodedInfo::kRGBA_Color);
+            break;
+        case JCS_EXT_BGRA:
+            encodedInfo = this->getEncodedInfo().makeColor(SkEncodedInfo::kBGRA_Color);
+            break;
+#endif
+        case JCS_CMYK:
+            encodedInfo = this->getEncodedInfo().makeColor(SkEncodedInfo::kInvertedCMYK_Color);
+            break;
+#ifdef TURBO_HAS_565
+        case JCS_RGB565:
+            encodedInfo = this->getEncodedInfo().makeColor(SkEncodedInfo::kUnknown_Color);
+            break;
+#endif
+        default:
+            SkASSERT(false);
+            break;
     }
 
     Options swizzlerOptions = options;
     if (options.fSubset) {
         // Use fSwizzlerSubset if this is a subset decode.  This is necessary in the case
         // where libjpeg-turbo provides a subset and then we need to subset it further.
         // Also, verify that fSwizzlerSubset is initialized and valid.
         SkASSERT(!fSwizzlerSubset.isEmpty() && fSwizzlerSubset.x() <= options.fSubset->x() &&
                 fSwizzlerSubset.width() == options.fSubset->width());
         swizzlerOptions.fSubset = &fSwizzlerSubset;
     }
-    fSwizzler.reset(SkSwizzler::CreateSwizzler(srcConfig, nullptr, dstInfo, swizzlerOptions));
+    fSwizzler.reset(SkSwizzler::CreateSwizzler(encodedInfo, nullptr, dstInfo, swizzlerOptions));
     SkASSERT(fSwizzler);
     fStorage.reset(get_row_bytes(fDecoderMgr->dinfo()));
     fSrcRow = fStorage.get();
 }
 
 SkSampler* SkJpegCodec::getSampler(bool createIfNecessary) {
     if (!createIfNecessary || fSwizzler) {
         SkASSERT(!fSwizzler || (fSrcRow && fStorage.get() == fSrcRow));
         return fSwizzler;
     }
@@ skipping 334 matching lines @@
 
         JDIMENSION linesRead = jpeg_read_raw_data(dinfo, yuv, numRowsPerBlock);
         if (linesRead < remainingRows) {
             // FIXME: Handle incomplete YUV decodes without signalling an error.
             return kInvalidInput;
         }
     }
 
     return kSuccess;
 }