2 * Copyright (c) 2013 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.
16 int file_is_ivf(struct VpxInputContext *input_ctx) {
20 // TODO(tomfinegan): This can eventually go away, but for now it's required
21 // because the means by which file types are detected differ in vpxdec and
23 rewind(input_ctx->file);
25 if (fread(raw_hdr, 1, 32, input_ctx->file) == 32) {
26 if (raw_hdr[0] == 'D' && raw_hdr[1] == 'K' &&
27 raw_hdr[2] == 'I' && raw_hdr[3] == 'F') {
30 if (mem_get_le16(raw_hdr + 4) != 0) {
31 fprintf(stderr, "Error: Unrecognized IVF version! This file may not"
35 input_ctx->fourcc = mem_get_le32(raw_hdr + 8);
36 input_ctx->width = mem_get_le16(raw_hdr + 12);
37 input_ctx->height = mem_get_le16(raw_hdr + 14);
38 input_ctx->framerate.numerator = mem_get_le32(raw_hdr + 16);
39 input_ctx->framerate.denominator = mem_get_le32(raw_hdr + 20);
41 /* Some versions of vpxenc used 1/(2*fps) for the timebase, so
42 * we can guess the framerate using only the timebase in this
43 * case. Other files would require reading ahead to guess the
44 * timebase, like we do for webm.
46 if (input_ctx->framerate.numerator < 1000) {
47 /* Correct for the factor of 2 applied to the timebase in the
50 if (input_ctx->framerate.numerator & 1)
51 input_ctx->framerate.denominator <<= 1;
53 input_ctx->framerate.numerator >>= 1;
55 /* Don't know FPS for sure, and don't have readahead code
56 * (yet?), so just default to 30fps.
58 input_ctx->framerate.numerator = 30;
59 input_ctx->framerate.denominator = 1;
65 rewind(input_ctx->file);
67 input_ctx->detect.position = 4;
72 int ivf_read_frame(struct VpxInputContext *input_ctx,
75 size_t *buffer_size) {
76 char raw_header[IVF_FRAME_HDR_SZ] = {0};
77 size_t frame_size = 0;
78 FILE *infile = input_ctx->file;
80 if (input_ctx->file_type != FILE_TYPE_IVF)
83 if (fread(raw_header, IVF_FRAME_HDR_SZ, 1, infile) != 1) {
85 warn("Failed to read frame size\n");
87 frame_size = mem_get_le32(raw_header);
89 if (frame_size > 256 * 1024 * 1024) {
90 warn("Read invalid frame size (%u)\n", (unsigned int)frame_size);
94 if (frame_size > *buffer_size) {
95 uint8_t *new_buffer = realloc(*buffer, 2 * frame_size);
99 *buffer_size = 2 * frame_size;
101 warn("Failed to allocate compressed data buffer\n");
108 if (fread(*buffer, 1, frame_size, infile) != frame_size) {
109 warn("Failed to read full frame\n");
113 *bytes_read = frame_size;