1 // Copyright 2014 Google Inc. All Rights Reserved.
2 //
3 // Use of this source code is governed by a BSD-style license
4 // that can be found in the COPYING file in the root of the source
5 // tree. An additional intellectual property rights grant can be found
6 // in the file PATENTS. All contributing project authors may
7 // be found in the AUTHORS file in the root of the source tree.
8 // -----------------------------------------------------------------------------
9 //
10 // WebP decode.
11 
12 #ifndef WEBP_IMAGEIO_WEBPDEC_H_
13 #define WEBP_IMAGEIO_WEBPDEC_H_
14 
15 #include "webp/decode.h"
16 
17 #ifdef __cplusplus
18 extern "C" {
19 #endif
20 
21 struct Metadata;
22 struct WebPPicture;
23 
24 //------------------------------------------------------------------------------
25 // WebP decoding
26 
27 // Prints an informative error message regarding decode failure of 'in_file'.
28 // 'status' is treated as a VP8StatusCode and if valid will be printed as a
29 // text string.
30 void PrintWebPError(const char* const in_file, int status);
31 
32 // Reads a WebP from 'in_file', returning the contents and size in 'data' and
33 // 'data_size'. If not NULL, 'bitstream' is populated using WebPGetFeatures().
34 // Returns true on success.
35 int LoadWebP(const char* const in_file,
36              const uint8_t** data, size_t* data_size,
37              WebPBitstreamFeatures* bitstream);
38 
39 // Decodes the WebP contained in 'data'.
40 // 'config' is a structure previously initialized by WebPInitDecoderConfig().
41 // 'config->output' should have the desired colorspace selected.
42 // Returns the decoder status. On success 'config->output' will contain the
43 // decoded picture.
44 VP8StatusCode DecodeWebP(const uint8_t* const data, size_t data_size,
45                          WebPDecoderConfig* const config);
46 
47 // Same as DecodeWebP(), but using the incremental decoder.
48 VP8StatusCode DecodeWebPIncremental(
49     const uint8_t* const data, size_t data_size,
50     WebPDecoderConfig* const config);
51 
52 //------------------------------------------------------------------------------
53 
54 // Decodes a WebP contained in 'data', returning the decoded output in 'pic'.
55 // Output is RGBA or YUVA, depending on pic->use_argb value.
56 // If 'keep_alpha' is true and the WebP has an alpha channel, the output is RGBA
57 // or YUVA. Otherwise, alpha channel is dropped and output is RGB or YUV.
58 // Returns true on success.
59 int ReadWebP(const uint8_t* const data, size_t data_size,
60              struct WebPPicture* const pic,
61              int keep_alpha, struct Metadata* const metadata);
62 
63 #ifdef __cplusplus
64 }    // extern "C"
65 #endif
66 
67 #endif  // WEBP_IMAGEIO_WEBPDEC_H_
68