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Diffstat (limited to 'media/libvpx/libvpx/examples/decode_to_md5.c')
-rw-r--r-- | media/libvpx/libvpx/examples/decode_to_md5.c | 132 |
1 files changed, 132 insertions, 0 deletions
diff --git a/media/libvpx/libvpx/examples/decode_to_md5.c b/media/libvpx/libvpx/examples/decode_to_md5.c new file mode 100644 index 0000000000..51959f37df --- /dev/null +++ b/media/libvpx/libvpx/examples/decode_to_md5.c @@ -0,0 +1,132 @@ +/* + * Copyright (c) 2010 The WebM project authors. All Rights Reserved. + * + * Use of this source code is governed by a BSD-style license + * that can be found in the LICENSE file in the root of the source + * tree. An additional intellectual property rights grant can be found + * in the file PATENTS. All contributing project authors may + * be found in the AUTHORS file in the root of the source tree. + */ + +// Frame-by-frame MD5 Checksum +// =========================== +// +// This example builds upon the simple decoder loop to show how checksums +// of the decoded output can be generated. These are used for validating +// decoder implementations against the reference implementation, for example. +// +// MD5 algorithm +// ------------- +// The Message-Digest 5 (MD5) is a well known hash function. We have provided +// an implementation derived from the RSA Data Security, Inc. MD5 Message-Digest +// Algorithm for your use. Our implmentation only changes the interface of this +// reference code. You must include the `md5_utils.h` header for access to these +// functions. +// +// Processing The Decoded Data +// --------------------------- +// Each row of the image is passed to the MD5 accumulator. First the Y plane +// is processed, then U, then V. It is important to honor the image's `stride` +// values. + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include "vpx/vp8dx.h" +#include "vpx/vpx_decoder.h" + +#include "../md5_utils.h" +#include "../tools_common.h" +#include "../video_reader.h" +#include "./vpx_config.h" + +static void get_image_md5(const vpx_image_t *img, unsigned char digest[16]) { + int plane, y; + MD5Context md5; + + MD5Init(&md5); + + for (plane = 0; plane < 3; ++plane) { + const unsigned char *buf = img->planes[plane]; + const int stride = img->stride[plane]; + const int w = plane ? (img->d_w + 1) >> 1 : img->d_w; + const int h = plane ? (img->d_h + 1) >> 1 : img->d_h; + + for (y = 0; y < h; ++y) { + MD5Update(&md5, buf, w); + buf += stride; + } + } + + MD5Final(digest, &md5); +} + +static void print_md5(FILE *stream, unsigned char digest[16]) { + int i; + + for (i = 0; i < 16; ++i) fprintf(stream, "%02x", digest[i]); +} + +static const char *exec_name; + +void usage_exit(void) { + fprintf(stderr, "Usage: %s <infile> <outfile>\n", exec_name); + exit(EXIT_FAILURE); +} + +int main(int argc, char **argv) { + int frame_cnt = 0; + FILE *outfile = NULL; + vpx_codec_ctx_t codec; + VpxVideoReader *reader = NULL; + const VpxVideoInfo *info = NULL; + const VpxInterface *decoder = NULL; + + exec_name = argv[0]; + + if (argc != 3) die("Invalid number of arguments."); + + reader = vpx_video_reader_open(argv[1]); + if (!reader) die("Failed to open %s for reading.", argv[1]); + + if (!(outfile = fopen(argv[2], "wb"))) + die("Failed to open %s for writing.", argv[2]); + + info = vpx_video_reader_get_info(reader); + + decoder = get_vpx_decoder_by_fourcc(info->codec_fourcc); + if (!decoder) die("Unknown input codec."); + + printf("Using %s\n", vpx_codec_iface_name(decoder->codec_interface())); + + if (vpx_codec_dec_init(&codec, decoder->codec_interface(), NULL, 0)) + die_codec(&codec, "Failed to initialize decoder"); + + while (vpx_video_reader_read_frame(reader)) { + vpx_codec_iter_t iter = NULL; + vpx_image_t *img = NULL; + size_t frame_size = 0; + const unsigned char *frame = + vpx_video_reader_get_frame(reader, &frame_size); + if (vpx_codec_decode(&codec, frame, (unsigned int)frame_size, NULL, 0)) + die_codec(&codec, "Failed to decode frame"); + + while ((img = vpx_codec_get_frame(&codec, &iter)) != NULL) { + unsigned char digest[16]; + + get_image_md5(img, digest); + print_md5(outfile, digest); + fprintf(outfile, " img-%dx%d-%04d.i420\n", img->d_w, img->d_h, + ++frame_cnt); + } + } + + printf("Processed %d frames.\n", frame_cnt); + if (vpx_codec_destroy(&codec)) die_codec(&codec, "Failed to destroy codec."); + + vpx_video_reader_close(reader); + + fclose(outfile); + return EXIT_SUCCESS; +} |