1 /*
2 * Copyright (c) 2010 The WebM project authors. All Rights Reserved.
3 *
4 * Use of this source code is governed by a BSD-style license
5 * that can be found in the LICENSE file in the root of the source
6 * tree. An additional intellectual property rights grant can be found
7 * in the file PATENTS. All contributing project authors may
8 * be found in the AUTHORS file in the root of the source tree.
9 */
10
11
12 // Simple Decoder
13 // ==============
14 //
15 // This is an example of a simple decoder loop. It takes an input file
16 // containing the compressed data (in IVF format), passes it through the
17 // decoder, and writes the decompressed frames to disk. Other decoder
18 // examples build upon this one.
19 //
20 // The details of the IVF format have been elided from this example for
21 // simplicity of presentation, as IVF files will not generally be used by
22 // your application. In general, an IVF file consists of a file header,
23 // followed by a variable number of frames. Each frame consists of a frame
24 // header followed by a variable length payload. The length of the payload
25 // is specified in the first four bytes of the frame header. The payload is
26 // the raw compressed data.
27 //
28 // Standard Includes
29 // -----------------
30 // For decoders, you only have to include `vpx_decoder.h` and then any
31 // header files for the specific codecs you use. In this case, we're using
32 // vp8. The `VPX_CODEC_DISABLE_COMPAT` macro can be defined to ensure
33 // strict compliance with the latest SDK by disabling some backwards
34 // compatibility features. Defining this macro is encouraged.
35 //
36 // Initializing The Codec
37 // ----------------------
38 // The decoder is initialized by the following code. This is an example for
39 // the VP8 decoder, but the code is analogous for all algorithms. Replace
40 // `vpx_codec_vp8_dx()` with a pointer to the interface exposed by the
41 // algorithm you want to use. The `cfg` argument is left as NULL in this
42 // example, because we want the algorithm to determine the stream
43 // configuration (width/height) and allocate memory automatically. This
44 // parameter is generally only used if you need to preallocate memory,
45 // particularly in External Memory Allocation mode.
46 //
47 // Decoding A Frame
48 // ----------------
49 // Once the frame has been read into memory, it is decoded using the
50 // `vpx_codec_decode` function. The call takes a pointer to the data
51 // (`frame`) and the length of the data (`frame_sz`). No application data
52 // is associated with the frame in this example, so the `user_priv`
53 // parameter is NULL. The `deadline` parameter is left at zero for this
54 // example. This parameter is generally only used when doing adaptive
55 // postprocessing.
56 //
57 // Codecs may produce a variable number of output frames for every call to
58 // `vpx_codec_decode`. These frames are retrieved by the
59 // `vpx_codec_get_frame` iterator function. The iterator variable `iter` is
60 // initialized to NULL each time `vpx_codec_decode` is called.
61 // `vpx_codec_get_frame` is called in a loop, returning a pointer to a
62 // decoded image or NULL to indicate the end of list.
63 //
64 // Processing The Decoded Data
65 // ---------------------------
66 // In this example, we simply write the encoded data to disk. It is
67 // important to honor the image's `stride` values.
68 //
69 // Cleanup
70 // -------
71 // The `vpx_codec_destroy` call frees any memory allocated by the codec.
72 //
73 // Error Handling
74 // --------------
75 // This example does not special case any error return codes. If there was
76 // an error, a descriptive message is printed and the program exits. With
77 // few exeptions, vpx_codec functions return an enumerated error status,
78 // with the value `0` indicating success.
79
80 #include <stdio.h>
81 #include <stdlib.h>
82 #include <string.h>
83
84 #define VPX_CODEC_DISABLE_COMPAT 1
85
86 #include "vpx/vp8dx.h"
87 #include "vpx/vpx_decoder.h"
88
89 #include "./tools_common.h"
90 #include "./video_reader.h"
91 #include "./vpx_config.h"
92
93 static const char *exec_name;
94
usage_exit()95 void usage_exit() {
96 fprintf(stderr, "Usage: %s <infile> <outfile>\n", exec_name);
97 exit(EXIT_FAILURE);
98 }
99
main(int argc,char ** argv)100 int main(int argc, char **argv) {
101 int frame_cnt = 0;
102 FILE *outfile = NULL;
103 vpx_codec_ctx_t codec;
104 VpxVideoReader *reader = NULL;
105 const VpxInterface *decoder = NULL;
106 const VpxVideoInfo *info = NULL;
107
108 exec_name = argv[0];
109
110 if (argc != 3)
111 die("Invalid number of arguments.");
112
113 reader = vpx_video_reader_open(argv[1]);
114 if (!reader)
115 die("Failed to open %s for reading.", argv[1]);
116
117 if (!(outfile = fopen(argv[2], "wb")))
118 die("Failed to open %s for writing.", argv[2]);
119
120 info = vpx_video_reader_get_info(reader);
121
122 decoder = get_vpx_decoder_by_fourcc(info->codec_fourcc);
123 if (!decoder)
124 die("Unknown input codec.");
125
126 printf("Using %s\n", vpx_codec_iface_name(decoder->interface()));
127
128 if (vpx_codec_dec_init(&codec, decoder->interface(), NULL, 0))
129 die_codec(&codec, "Failed to initialize decoder.");
130
131 while (vpx_video_reader_read_frame(reader)) {
132 vpx_codec_iter_t iter = NULL;
133 vpx_image_t *img = NULL;
134 size_t frame_size = 0;
135 const unsigned char *frame = vpx_video_reader_get_frame(reader,
136 &frame_size);
137 if (vpx_codec_decode(&codec, frame, (unsigned int)frame_size, NULL, 0))
138 die_codec(&codec, "Failed to decode frame.");
139
140 while ((img = vpx_codec_get_frame(&codec, &iter)) != NULL) {
141 vpx_img_write(img, outfile);
142 ++frame_cnt;
143 }
144 }
145
146 printf("Processed %d frames.\n", frame_cnt);
147 if (vpx_codec_destroy(&codec))
148 die_codec(&codec, "Failed to destroy codec");
149
150 printf("Play: ffplay -f rawvideo -pix_fmt yuv420p -s %dx%d %s\n",
151 info->frame_width, info->frame_height, argv[2]);
152
153 vpx_video_reader_close(reader);
154
155 fclose(outfile);
156
157 return EXIT_SUCCESS;
158 }
159