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Merge "ReadWebP: avoid conversion to ARGB if final format is YUVA"

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This commit is contained in:
Pascal Massimino 2016-05-27 05:51:15 +00:00 committed by Gerrit Code Review
commit 77cad88589
4 changed files with 56 additions and 22 deletions
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23
examples/cwebp.c
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@ -50,13 +50,12 @@ static int verbose = 0;
static int ReadYUV(const uint8_t* const data, size_t data_size,
WebPPicture* const pic) {
int y;
const int use_argb = pic->use_argb;
const int uv_width = (pic->width + 1) / 2;
const int uv_height = (pic->height + 1) / 2;
const int y_plane_size = pic->width * pic->height;
const int uv_plane_size = uv_width * uv_height;
const size_t expected_data_size =
pic->width * pic->height + 2 * uv_plane_size;
const size_t expected_data_size = y_plane_size + 2 * uv_plane_size;
if (data_size != expected_data_size) {
fprintf(stderr,
@ -67,18 +66,12 @@ static int ReadYUV(const uint8_t* const data, size_t data_size,
pic->use_argb = 0;
if (!WebPPictureAlloc(pic)) return 0;
for (y = 0; y < pic->height; ++y) {
memcpy(pic->y + y * pic->y_stride, data + y * pic->width,
pic->width * sizeof(*pic->y));
}
for (y = 0; y < uv_height; ++y) {
const uint8_t* const uv_data = data + pic->height * pic->y_stride;
memcpy(pic->u + y * pic->uv_stride, uv_data + y * uv_width,
uv_width * sizeof(*uv_data));
memcpy(pic->v + y * pic->uv_stride, uv_data + y * uv_width + uv_plane_size,
uv_width * sizeof(*uv_data));
}
ExUtilCopyPlane(data, pic->width, pic->y, pic->y_stride,
pic->width, pic->height);
ExUtilCopyPlane(data + y_plane_size, uv_width,
pic->u, pic->uv_stride, uv_width, uv_height);
ExUtilCopyPlane(data + y_plane_size + uv_plane_size, uv_width,
pic->v, pic->uv_stride, uv_width, uv_height);
return use_argb ? WebPPictureYUVAToARGB(pic) : 1;
}

11
examples/example_util.c
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@ -268,3 +268,14 @@ VP8StatusCode ExUtilDecodeWebPIncremental(
}
// -----------------------------------------------------------------------------
void ExUtilCopyPlane(const uint8_t* src, int src_stride,
uint8_t* dst, int dst_stride, int width, int height) {
while (height-- > 0) {
memcpy(dst, src, width * sizeof(*dst));
src += src_stride;
dst += dst_stride;
}
}
// -----------------------------------------------------------------------------

6
examples/example_util.h
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@ -53,6 +53,12 @@ int ExUtilReadFromStdin(const uint8_t** data, size_t* data_size);
int ExUtilWriteFile(const char* const file_name,
const uint8_t* data, size_t data_size);
//------------------------------------------------------------------------------
// Copy width x height pixels from 'src' to 'dst' honoring the strides.
void ExUtilCopyPlane(const uint8_t* src, int src_stride,
uint8_t* dst, int dst_stride, int width, int height);
//------------------------------------------------------------------------------
// WebP decoding

32
examples/webpdec.c
View File

@ -45,18 +45,42 @@ int ReadWebP(const uint8_t* const data, size_t data_size,
}
{
const int has_alpha = keep_alpha && bitstream->has_alpha;
// TODO(skal): use MODE_YUV(A), depending on the expected
// input pic->use_argb. This would save some conversion steps.
if (pic->use_argb) {
output_buffer->colorspace = has_alpha ? MODE_RGBA : MODE_RGB;
} else {
output_buffer->colorspace = has_alpha ? MODE_YUVA : MODE_YUV;
}
status = ExUtilDecodeWebP(data, data_size, 0, &config);
if (status == VP8_STATUS_OK) {
const uint8_t* const rgba = output_buffer->u.RGBA.rgba;
const int stride = output_buffer->u.RGBA.stride;
pic->width = output_buffer->width;
pic->height = output_buffer->height;
if (pic->use_argb) {
const uint8_t* const rgba = output_buffer->u.RGBA.rgba;
const int stride = output_buffer->u.RGBA.stride;
ok = has_alpha ? WebPPictureImportRGBA(pic, rgba, stride)
: WebPPictureImportRGB(pic, rgba, stride);
} else {
pic->colorspace = has_alpha ? WEBP_YUV420A : WEBP_YUV420;
ok = WebPPictureAlloc(pic);
if (!ok) {
status = VP8_STATUS_OUT_OF_MEMORY;
} else {
const WebPYUVABuffer* const yuva = &output_buffer->u.YUVA;
const int uv_width = (pic->width + 1) >> 1;
const int uv_height = (pic->height + 1) >> 1;
ExUtilCopyPlane(yuva->y, yuva->y_stride,
pic->y, pic->y_stride, pic->width, pic->height);
ExUtilCopyPlane(yuva->u, yuva->u_stride,
pic->u, pic->uv_stride, uv_width, uv_height);
ExUtilCopyPlane(yuva->v, yuva->v_stride,
pic->v, pic->uv_stride, uv_width, uv_height);
if (has_alpha) {
ExUtilCopyPlane(yuva->a, yuva->a_stride,
pic->a, pic->a_stride, pic->width, pic->height);
}
}
}
}
}