libwebp/examples/jpegdec.h
Pascal Massimino 7861578bd6 for ReadXXXX() image-readers, use the value of pic->use_argb
This is to infer the needed conversion to YUV(A) or RGB(A).

This is useful to avoid some conversion steps between ARGB and YUVA.
For instance, if the input file is a JPEG, we decode to RGB and
convert to YUV right away, without the intermediate step to ARGB.

The only caveat is that cropping/scaling might give slightly different result,
because of YUV420 downsampling. Therefore, we omit this feature
at cwebp level, when -crop or -rescale is used.

Change-Id: I5a3abe5108982f2a4570e841e3d9baffc73f5bee
2015-10-27 22:54:11 +01:00

36 lines
1019 B
C

// Copyright 2012 Google Inc. All Rights Reserved.
//
// Use of this source code is governed by a BSD-style license
// that can be found in the COPYING file in the root of the source
// tree. An additional intellectual property rights grant can be found
// in the file PATENTS. All contributing project authors may
// be found in the AUTHORS file in the root of the source tree.
// -----------------------------------------------------------------------------
//
// JPEG decode.
#ifndef WEBP_EXAMPLES_JPEGDEC_H_
#define WEBP_EXAMPLES_JPEGDEC_H_
#include <stdio.h>
#include "webp/types.h"
#ifdef __cplusplus
extern "C" {
#endif
struct Metadata;
struct WebPPicture;
// Reads a JPEG from 'in_file', returning the decoded output in 'pic'.
// The output is RGB or YUV depending on pic->use_argb value.
// Returns true on success.
int ReadJPEG(FILE* in_file, struct WebPPicture* const pic,
struct Metadata* const metadata);
#ifdef __cplusplus
} // extern "C"
#endif
#endif // WEBP_EXAMPLES_JPEGDEC_H_