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#include "vpx/vp8dx.h"
37#include "vpx/vpx_decoder.h"
38
39#include "./md5_utils.h"
40#include "./tools_common.h"
41#include "./video_reader.h"
42#include "./vpx_config.h"
43
44static void get_image_md5(const vpx_image_t *img, unsigned char digest[16]) {
45  int plane, y;
46  MD5Context md5;
47
48  MD5Init(&md5);
49
50  for (plane = 0; plane < 3; ++plane) {
51    const unsigned char *buf = img->planes[plane];
52    const int stride = img->stride[plane];
53    const int w = plane ? (img->d_w + 1) >> 1 : img->d_w;
54    const int h = plane ? (img->d_h + 1) >> 1 : img->d_h;
55
56    for (y = 0; y < h; ++y) {
57      MD5Update(&md5, buf, w);
58      buf += stride;
59    }
60  }
61
62  MD5Final(digest, &md5);
63}
64
65static void print_md5(FILE *stream, unsigned char digest[16]) {
66  int i;
67
68  for (i = 0; i < 16; ++i)
69    fprintf(stream, "%02x", digest[i]);
70}
71
72static const char *exec_name;
73
74void usage_exit() {
75  fprintf(stderr, "Usage: %s <infile> <outfile>\n", exec_name);
76  exit(EXIT_FAILURE);
77}
78
79int main(int argc, char **argv) {
80  int frame_cnt = 0;
81  FILE *outfile = NULL;
82  vpx_codec_ctx_t codec;
83  VpxVideoReader *reader = NULL;
84  const VpxVideoInfo *info = NULL;
85  const VpxInterface *decoder = NULL;
86
87  exec_name = argv[0];
88
89  if (argc != 3)
90    die("Invalid number of arguments.");
91
92  reader = vpx_video_reader_open(argv[1]);
93  if (!reader)
94    die("Failed to open %s for reading.", argv[1]);
95
96  if (!(outfile = fopen(argv[2], "wb")))
97    die("Failed to open %s for writing.", argv[2]);
98
99  info = vpx_video_reader_get_info(reader);
100
101  decoder = get_vpx_decoder_by_fourcc(info->codec_fourcc);
102  if (!decoder)
103    die("Unknown input codec.");
104
105  printf("Using %s\n", vpx_codec_iface_name(decoder->codec_interface()));
106
107  if (vpx_codec_dec_init(&codec, decoder->codec_interface(), NULL, 0))
108    die_codec(&codec, "Failed to initialize decoder");
109
110  while (vpx_video_reader_read_frame(reader)) {
111    vpx_codec_iter_t iter = NULL;
112    vpx_image_t *img = NULL;
113    size_t frame_size = 0;
114    const unsigned char *frame = vpx_video_reader_get_frame(reader,
115                                                            &frame_size);
116    if (vpx_codec_decode(&codec, frame, (unsigned int)frame_size, NULL, 0))
117      die_codec(&codec, "Failed to decode frame");
118
119    while ((img = vpx_codec_get_frame(&codec, &iter)) != NULL) {
120      unsigned char digest[16];
121
122      get_image_md5(img, digest);
123      print_md5(outfile, digest);
124      fprintf(outfile, "  img-%dx%d-%04d.i420\n",
125              img->d_w, img->d_h, ++frame_cnt);
126    }
127  }
128
129  printf("Processed %d frames.\n", frame_cnt);
130  if (vpx_codec_destroy(&codec))
131    die_codec(&codec, "Failed to destroy codec.");
132
133  vpx_video_reader_close(reader);
134
135  fclose(outfile);
136  return EXIT_SUCCESS;
137}
138