2 * Copyright (c) 2010 The WebM project authors. All Rights Reserved.
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.
11 // Frame-by-frame MD5 Checksum
12 // ===========================
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.
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
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`
36 #include "vpx/vp8dx.h"
37 #include "vpx/vpx_decoder.h"
39 #include "../md5_utils.h"
40 #include "../tools_common.h"
41 #include "../video_reader.h"
42 #include "./vpx_config.h"
44 static void get_image_md5(const vpx_image_t *img, unsigned char digest[16]) {
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;
56 for (y = 0; y < h; ++y) {
57 MD5Update(&md5, buf, w);
62 MD5Final(digest, &md5);
65 static void print_md5(FILE *stream, unsigned char digest[16]) {
68 for (i = 0; i < 16; ++i)
69 fprintf(stream, "%02x", digest[i]);
72 static const char *exec_name;
74 void usage_exit(void) {
75 fprintf(stderr, "Usage: %s <infile> <outfile>\n", exec_name);
79 int main(int argc, char **argv) {
82 vpx_codec_ctx_t codec;
83 VpxVideoReader *reader = NULL;
84 const VpxVideoInfo *info = NULL;
85 const VpxInterface *decoder = NULL;
90 die("Invalid number of arguments.");
92 reader = vpx_video_reader_open(argv[1]);
94 die("Failed to open %s for reading.", argv[1]);
96 if (!(outfile = fopen(argv[2], "wb")))
97 die("Failed to open %s for writing.", argv[2]);
99 info = vpx_video_reader_get_info(reader);
101 decoder = get_vpx_decoder_by_fourcc(info->codec_fourcc);
103 die("Unknown input codec.");
105 printf("Using %s\n", vpx_codec_iface_name(decoder->codec_interface()));
107 if (vpx_codec_dec_init(&codec, decoder->codec_interface(), NULL, 0))
108 die_codec(&codec, "Failed to initialize decoder");
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,
116 if (vpx_codec_decode(&codec, frame, (unsigned int)frame_size, NULL, 0))
117 die_codec(&codec, "Failed to decode frame");
119 while ((img = vpx_codec_get_frame(&codec, &iter)) != NULL) {
120 unsigned char digest[16];
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);
129 printf("Processed %d frames.\n", frame_cnt);
130 if (vpx_codec_destroy(&codec))
131 die_codec(&codec, "Failed to destroy codec.");
133 vpx_video_reader_close(reader);