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// Frame-by-frame MD5 Checksum
12// ===========================
13//
14// This example builds upon the simple decoder loop to show how checksums
15// of the decoded output can be generated. These are used for validating
16// decoder implementations against the reference implementation, for example.
17//
18// MD5 algorithm
19// -------------
20// The Message-Digest 5 (MD5) is a well known hash function. We have provided
21// an implementation derived from the RSA Data Security, Inc. MD5 Message-Digest
22// Algorithm for your use. Our implmentation only changes the interface of this
23// reference code. You must include the `md5_utils.h` header for access to these
24// functions.
25//
26// Processing The Decoded Data
27// ---------------------------
28// Each row of the image is passed to the MD5 accumulator. First the Y plane
29// is processed, then U, then V. It is important to honor the image's `stride`
30// values.
31
32#include <stdio.h>
33#include <stdlib.h>
34#include <string.h>
35
36#define VPX_CODEC_DISABLE_COMPAT 1
37
38#include "vpx/vp8dx.h"
39#include "vpx/vpx_decoder.h"
40
41#include "./md5_utils.h"
42#include "./tools_common.h"
43#include "./video_reader.h"
44#include "./vpx_config.h"
45
46static void get_image_md5(const vpx_image_t *img, unsigned char digest[16]) {
47  int plane, y;
48  MD5Context md5;
49
50  MD5Init(&md5);
51
52  for (plane = 0; plane < 3; ++plane) {
53    const unsigned char *buf = img->planes[plane];
54    const int stride = img->stride[plane];
55    const int w = plane ? (img->d_w + 1) >> 1 : img->d_w;
56    const int h = plane ? (img->d_h + 1) >> 1 : img->d_h;
57
58    for (y = 0; y < h; ++y) {
59      MD5Update(&md5, buf, w);
60      buf += stride;
61    }
62  }
63
64  MD5Final(digest, &md5);
65}
66
67static void print_md5(FILE *stream, unsigned char digest[16]) {
68  int i;
69
70  for (i = 0; i < 16; ++i)
71    fprintf(stream, "%02x", digest[i]);
72}
73
74static const char *exec_name;
75
76void usage_exit() {
77  fprintf(stderr, "Usage: %s <infile> <outfile>\n", exec_name);
78  exit(EXIT_FAILURE);
79}
80
81int main(int argc, char **argv) {
82  int frame_cnt = 0;
83  FILE *outfile = NULL;
84  vpx_codec_ctx_t codec;
85  VpxVideoReader *reader = NULL;
86  const VpxVideoInfo *info = NULL;
87  const VpxInterface *decoder = NULL;
88
89  exec_name = argv[0];
90
91  if (argc != 3)
92    die("Invalid number of arguments.");
93
94  reader = vpx_video_reader_open(argv[1]);
95  if (!reader)
96    die("Failed to open %s for reading.", argv[1]);
97
98  if (!(outfile = fopen(argv[2], "wb")))
99    die("Failed to open %s for writing.", argv[2]);
100
101  info = vpx_video_reader_get_info(reader);
102
103  decoder = get_vpx_decoder_by_fourcc(info->codec_fourcc);
104  if (!decoder)
105    die("Unknown input codec.");
106
107  printf("Using %s\n", vpx_codec_iface_name(decoder->interface()));
108
109  if (vpx_codec_dec_init(&codec, decoder->interface(), NULL, 0))
110    die_codec(&codec, "Failed to initialize decoder");
111
112  while (vpx_video_reader_read_frame(reader)) {
113    vpx_codec_iter_t iter = NULL;
114    vpx_image_t *img = NULL;
115    size_t frame_size = 0;
116    const unsigned char *frame = vpx_video_reader_get_frame(reader,
117                                                            &frame_size);
118    if (vpx_codec_decode(&codec, frame, (unsigned int)frame_size, NULL, 0))
119      die_codec(&codec, "Failed to decode frame");
120
121    while ((img = vpx_codec_get_frame(&codec, &iter)) != NULL) {
122      unsigned char digest[16];
123
124      get_image_md5(img, digest);
125      print_md5(outfile, digest);
126      fprintf(outfile, "  img-%dx%d-%04d.i420\n",
127              img->d_w, img->d_h, ++frame_cnt);
128    }
129  }
130
131  printf("Processed %d frames.\n", frame_cnt);
132  if (vpx_codec_destroy(&codec))
133    die_codec(&codec, "Failed to destroy codec.");
134
135  vpx_video_reader_close(reader);
136
137  fclose(outfile);
138  return EXIT_SUCCESS;
139}
140