Prototype of RAW decoding in Skia.

src/codec/SkRawCodec.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 "SkRawCodec.h"
+#include "SkCodecPriv.h"
+#include "SkColorPriv.h"
+#include "SkStream.h"
+#include "SkTemplates.h"
+#include "SkTypes.h"
+#include "SkSwizzler.h"
+#include "SkJpegCodec.h"
+
+#include "dng_color_space.h"
+#include "dng_exceptions.h"
+#include "dng_host.h"
+#include "dng_info.h"
+#include "dng_render.h"
+
+#include "src/piex.h"
+
+#include <cstring>
+#include <cmath>
+#include <vector>
+
+namespace {
+
+class SkDngStream : public dng_stream {
+   public:
+    explicit SkDngStream(SkStream* stream)
+        : fData(stream->getMemoryBase())

[scroggo, 2015/12/18 15:56:26]

I brought this up in the other code review (see
https://codereview.chromium.org/1459473007/diff/1/src/codec/SkRawCodec.cpp#ne...)
- you cannot depend on this.

[yujieqin, 2016/01/06 18:47:19]

Done for the DNG case. 

We still plan to do more clever stuff for the PiexStream case in next round.

+        , fDataSize(stream->getLength()) {}

[scroggo, 2015/12/18 15:56:26]

ditto.

[yujieqin, 2016/01/06 18:47:19]

Done.

+
+    ~SkDngStream() override {}
+
+   protected:
+    uint64 DoGetLength() override { return fDataSize; }
+    void DoRead(void* data, uint32 count, uint64 offset) override {
+        if (fDataSize < offset + count) {
+            ThrowReadFile();
+        }
+        std::memcpy(data, 

[scroggo, 2015/12/18 15:56:27]

Why not just: 

memcpy(data, reinterpret_cast<const uint8*>(fData) + offset, count);

[yujieqin, 2016/01/06 18:47:19]

Done.

+                    reinterpret_cast<const uint8*>(fData) + offset, count);
+    }
+
+   private:
+    const void* fData;
+    size_t fDataSize;
+};
+
+class SkPiexStream : public ::piex::StreamInterface {
+   public:
+    explicit SkPiexStream(SkStream* stream)
+        : fData(stream->getMemoryBase())
+        , fDataSize(stream->getLength()) {}
+
+    ::piex::Error GetData(const size_t offset, const size_t length,
+                          uint8* data) override {
+        if (offset >= fDataSize || fDataSize - offset < length) {
+          return ::piex::Error::kFail;
+        }
+        std::memcpy(data,
+                    reinterpret_cast<const uint8*>(fData) + offset, length);
+        return ::piex::Error::kOk;
+    }
+
+   private:
+    const void* fData;
+    size_t fDataSize;
+};
+
+bool IsDng(SkStream* data) {
+    try {
+        SkDngStream stream(data);

[scroggo, 2015/12/18 15:56:27]

Please see comments in
https://codereview.chromium.org/1459473007/diff/20001/src/codec/SkRawCodec.cp...

[yujieqin, 2016/01/06 18:47:19]

code removed.

+        dng_host host;
+        dng_info info;
+        info.Parse(host, stream);
+        info.PostParse(host);
+        const bool ok= info.IsValidDNG();
+        return ok;
+    } catch (...) {  // Handle all kinds of exceptions as "false".
+        return false;
+    }
+}
+
+bool IsPiexSupportedRaw(SkStream* data) {
+    SkPiexStream stream(data);
+    const bool ok = ::piex::IsRaw(&stream);
+    return ok;
+}
+
+bool ReadDng(dng_stream* stream, dng_host* host, dng_info* info,
+             std::unique_ptr<dng_negative>* negative) {
+    const uint32 kPreferredSize = 0;
+    const uint32 kMinimumSize = 0;
+    const uint32 kMaximumSize = 0;
+    try {
+        host->SetPreferredSize(kPreferredSize);
+        host->SetMinimumSize(kMinimumSize);
+        host->SetMaximumSize(kMaximumSize);
+
+        host->ValidateSizes();
+
+        // Read stage 1 image into the negative.
+        {
+            info->Parse(*host, *stream);
+            info->PostParse(*host);
+
+            if (!info->IsValidDNG()) {
+                return false;
+            }
+
+            negative->reset(host->Make_dng_negative());
+            (*negative)->Parse(*host, *stream, *info);
+            (*negative)->PostParse(*host, *stream, *info);
+        }
+
+        (*negative)->SynchronizeMetadata();
+    } catch (const dng_exception& exception) {
+        printf("ReadDng faile with dng_exception\n");
+        return false;
+    } catch (...) {
+        printf("ReadDng faile with unknown exception\n");
+        return false;
+    }
+
+    return true;
+}
+
+bool PrepareStage3(dng_stream* stream, dng_host* host, dng_info* info,
+                   dng_negative* negative) {
+    if (negative->Stage3Image() == nullptr) {
+        negative->ReadStage1Image(*host, *stream, *info);
+
+        if (info->fMaskIndex != -1) {
+            negative->ReadTransparencyMask(*host, *stream, *info);
+        }
+
+        negative->ValidateRawImageDigest(*host);
+        if (negative->IsDamaged()) {
+                printf("PrepareStage3 Fail: negative->IsDamaged\n");
+            return false;
+        }
+
+        const int32 kMosaicPlane = -1;
+        negative->BuildStage2Image(*host);
+        negative->BuildStage3Image(*host, kMosaicPlane);
+    }
+
+    return true;
+}
+
+}  // namespace
+
+bool SkRawCodec::IsRaw(SkStream* stream) {
+    const bool ok = IsDng(stream) || IsPiexSupportedRaw(stream);
+    return ok;
+}
+
+SkCodec* SkRawCodec::NewFromStream(SkStream* data) {
+    if (IsDng(data)) {
+        SkDngStream stream(data);
+        dng_host host;
+        dng_info info;
+        std::unique_ptr<dng_negative> negative;
+        if (!ReadDng(&stream, &host, &info, &negative) &&
+            !PrepareStage3(&stream, &host, &info, negative.get())) {
+            printf("NewFromStream Dng SDK Failed.\n");
+            return nullptr;
+        }
+        const SkImageInfo& imageInfo = SkImageInfo::Make(
+            negative->DefaultCropSizeH().As_real64(),
+            negative->DefaultCropSizeV().As_real64(), kRGBA_8888_SkColorType,
+            kOpaque_SkAlphaType);
+        return new SkRawCodec(imageInfo, data);
+    } else if (IsPiexSupportedRaw(data)) {
+        ::piex::PreviewImageData imageData;
+        SkPiexStream stream(data);
+        ::piex::Error error = ::piex::GetPreviewImageData(&stream, &imageData);
+        if (error != ::piex::Error::kOk) {
+            printf("NewFromStream Piex Failed.\n");
+            return nullptr;
+        }
+
+        if (!data->rewind()) {
+            printf("Failed to rewind the stream.\n");
+            return nullptr;
+        }
+
+        data->skip(imageData.jpeg_offset);
+        std::vector<unsigned char>
+            buffer_jpeg_head(std::min(3u, imageData.jpeg_length));
+        data->read(static_cast<void*>(buffer_jpeg_head.data()),
+                   buffer_jpeg_head.size());
+        if (!SkJpegCodec::IsJpeg(static_cast<void*>(buffer_jpeg_head.data()),
+                                 buffer_jpeg_head.size())) {
+            printf("SkRawCodec Piex -> SkJpegCodec::IsJpeg failed.\n");
+            return nullptr;
+        }
+
+        if (!data->rewind()) {
+            printf("Failed to rewind the stream.\n");
+            return nullptr;
+        }
+        data->skip(imageData.jpeg_offset);
+        SkCodec* newCodec = SkJpegCodec::NewFromStream(data);
+        if (newCodec == nullptr) {
+          printf("SkRawCodec Piex -> SkJpegCodec is nullptr!\n");
+        }
+        return newCodec;
+    }
+
+   return nullptr;
+}
+
+SkCodec::Result SkRawCodec::onGetPixels(const SkImageInfo& requestedInfo, void* dst,
+                                        size_t dstRowBytes, const Options& options,
+                                        SkPMColor ctable[], int* ctableCount,
+                                        int* rowsDecoded) {
+  const int width = requestedInfo.width();
+  const int height = requestedInfo.height();
+  if (IsDng(this->stream())) {
+    std::unique_ptr<dng_image> finalDngImage;
+    try {
+      SkDngStream stream(this->stream());
+      dng_host host;
+      dng_info info;
+      std::unique_ptr<dng_negative> negative;
+      if (!ReadDng(&stream, &host, &info, &negative) ||
+          !PrepareStage3(&stream, &host, &info, negative.get())) {
+        printf("onGetPixels faile on Prepare\n");

[msarett, 2015/12/18 16:26:13]

nit: Spelling

[yujieqin, 2016/01/06 18:47:19]

code for debugging is removed.

+        return kInvalidInput;
+      }
+      
+      dng_render render(host, *negative);
+      render.SetFinalSpace(dng_space_sRGB::Get());
+      render.SetFinalPixelType(ttByte);
+      
+      finalDngImage.reset(render.Render());
+    } catch (const dng_exception& exception) {
+      printf("onGetPixels faile with dng_exception\n");

[msarett, 2015/12/18 16:26:13]

nit: Spelling

[yujieqin, 2016/01/06 18:47:19]

code for debugging is removed.

+      return kInvalidInput;
+    } catch (...) {
+      printf("onGetPixels faile with unknown exception\n");

[msarett, 2015/12/18 16:26:12]

nit: Spelling

[yujieqin, 2016/01/06 18:47:19]

code for debugging is removed.

+      return kInvalidInput;
+    }
+    
+    void* dstRow = dst;
+    uint8 srcRow[width * 3];
+    std::unique_ptr<SkSwizzler> swizzler(
+        SkSwizzler::CreateSwizzler(SkSwizzler::kRGB, nullptr, requestedInfo, options));
+    if (!swizzler) {
+      printf("onGetPixels swizzler failed\n");
+      return kInvalidInput;
+    }
+    for (int i = 0; i < height; ++i) {
+      dng_pixel_buffer buffer;
+      buffer.fData = &srcRow[0];
+      buffer.fArea = dng_rect(i, 0, i + 1, width);
+      buffer.fPlane = 0;
+      buffer.fPlanes = 3;
+      buffer.fColStep = buffer.fPlanes;
+      buffer.fPlaneStep = 1;
+      buffer.fPixelType = ttByte;
+      buffer.fPixelSize = sizeof(uint8);
+      buffer.fRowStep = sizeof(srcRow);
+      finalDngImage->Get(buffer, dng_image::edge_zero);
+      swizzler->swizzle(dstRow, &srcRow[0]);
+      dstRow = SkTAddOffset<void>(dstRow, dstRowBytes);
+    }
+    return kSuccess;
+  }
+
+  return kUnimplemented;
+}
+
+SkRawCodec::SkRawCodec(const SkImageInfo& srcInfo, SkStream* stream)
+    : INHERITED(srcInfo, stream) {}
+