examples/decode_to_md5.c

   1 /*
   2  * Copyright (c) 2016, Alliance for Open Media. All rights reserved
   3  *
   4  * This source code is subject to the terms of the BSD 2 Clause License and
   5  * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
   6  * was not distributed with this source code in the LICENSE file, you can
   7  * obtain it at www.aomedia.org/license/software. If the Alliance for Open
   8  * Media Patent License 1.0 was not distributed with this source code in the
   9  * PATENTS file, you can obtain it at www.aomedia.org/license/patent.
  10  */
  11
  12 // Frame-by-frame MD5 Checksum
  13 // ===========================
  14 //
  15 // This example builds upon the simple decoder loop to show how checksums
  16 // of the decoded output can be generated. These are used for validating
  17 // decoder implementations against the reference implementation, for example.
  18 //
  19 // MD5 algorithm
  20 // -------------
  21 // The Message-Digest 5 (MD5) is a well known hash function. We have provided
  22 // an implementation derived from the RSA Data Security, Inc. MD5 Message-Digest
  23 // Algorithm for your use. Our implmentation only changes the interface of this
  24 // reference code. You must include the `md5_utils.h` header for access to these
  25 // functions.
  26 //
  27 // Processing The Decoded Data
  28 // ---------------------------
  29 // Each row of the image is passed to the MD5 accumulator. First the Y plane
  30 // is processed, then U, then V. It is important to honor the image's `stride`
  31 // values.
  32
  33 #include <stdio.h>
  34 #include <stdlib.h>
  35 #include <string.h>
  36
  37 #include "aom/aom_decoder.h"
  38 #include "aom/aomdx.h"
  39 #include "common/md5_utils.h"
  40 #include "common/tools_common.h"
  41 #include "common/video_reader.h"
  42
  43 static void get_image_md5(const aom_image_t *img, unsigned char digest[16]) {
  44   int plane, y;
  45   MD5Context md5;
  46
  47   MD5Init(&md5);
  48
  49   for (plane = 0; plane < 3; ++plane) {
  50     const unsigned char *buf = img->planes[plane];
  51     const int stride = img->stride[plane];
  52     const int w = plane ? (img->d_w + 1) >> 1 : img->d_w;
  53     const int h = plane ? (img->d_h + 1) >> 1 : img->d_h;
  54
  55     for (y = 0; y < h; ++y) {
  56       MD5Update(&md5, buf, w);
  57       buf += stride;
  58     }
  59   }
  60
  61   MD5Final(digest, &md5);
  62 }
  63
  64 static void print_md5(FILE *stream, unsigned char digest[16]) {
  65   int i;
  66
  67   for (i = 0; i < 16; ++i) fprintf(stream, "%02x", digest[i]);
  68 }
  69
  70 static const char *exec_name;
  71
  72 void usage_exit(void) {
  73   fprintf(stderr, "Usage: %s <infile> <outfile>\n", exec_name);
  74   exit(EXIT_FAILURE);
  75 }
  76
  77 int main(int argc, char **argv) {
  78   int frame_cnt = 0;
  79   FILE *outfile = NULL;
  80   aom_codec_ctx_t codec;
  81   AvxVideoReader *reader = NULL;
  82   const AvxVideoInfo *info = NULL;
  83   const AvxInterface *decoder = NULL;
  84
  85   exec_name = argv[0];
  86
  87   if (argc != 3) die("Invalid number of arguments.");
  88
  89   reader = aom_video_reader_open(argv[1]);
  90   if (!reader) die("Failed to open %s for reading.", argv[1]);
  91
  92   if (!(outfile = fopen(argv[2], "wb")))
  93     die("Failed to open %s for writing.", argv[2]);
  94
  95   info = aom_video_reader_get_info(reader);
  96
  97   decoder = get_aom_decoder_by_fourcc(info->codec_fourcc);
  98   if (!decoder) die("Unknown input codec.");
  99
 100   printf("Using %s\n", aom_codec_iface_name(decoder->codec_interface()));
 101
 102   if (aom_codec_dec_init(&codec, decoder->codec_interface(), NULL, 0))
 103     die_codec(&codec, "Failed to initialize decoder");
 104
 105   while (aom_video_reader_read_frame(reader)) {
 106     aom_codec_iter_t iter = NULL;
 107     aom_image_t *img = NULL;
 108     size_t frame_size = 0;
 109     const unsigned char *frame =
 110         aom_video_reader_get_frame(reader, &frame_size);
 111     if (aom_codec_decode(&codec, frame, frame_size, NULL))
 112       die_codec(&codec, "Failed to decode frame");
 113
 114     while ((img = aom_codec_get_frame(&codec, &iter)) != NULL) {
 115       unsigned char digest[16];
 116
 117       get_image_md5(img, digest);
 118       print_md5(outfile, digest);
 119       fprintf(outfile, "  img-%dx%d-%04d.i420\n", img->d_w, img->d_h,
 120               ++frame_cnt);
 121     }
 122   }
 123
 124   printf("Processed %d frames.\n", frame_cnt);
 125   if (aom_codec_destroy(&codec)) die_codec(&codec, "Failed to destroy codec.");
 126
 127   aom_video_reader_close(reader);
 128
 129   fclose(outfile);
 130   return EXIT_SUCCESS;
 131 }