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/*
* Copyright (c) 2013 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.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "vpx_ports/mem_ops.h"
#include "./ivfdec.h"
static const char *IVF_SIGNATURE = "DKIF";
static void fix_framerate(int *num, int *den) {
// Some versions of vpxenc used 1/(2*fps) for the timebase, so
// we can guess the framerate using only the timebase in this
// case. Other files would require reading ahead to guess the
// timebase, like we do for webm.
if (*den > 0 && *den < 1000000000 && *num > 0 && *num < 1000) {
// Correct for the factor of 2 applied to the timebase in the encoder.
if (*num & 1)
*den *= 2;
else
*num /= 2;
} else {
// Don't know FPS for sure, and don't have readahead code
// (yet?), so just default to 30fps.
*num = 30;
*den = 1;
}
}
int file_is_ivf(struct VpxInputContext *input_ctx) {
char raw_hdr[32];
int is_ivf = 0;
if (fread(raw_hdr, 1, 32, input_ctx->file) == 32) {
if (memcmp(IVF_SIGNATURE, raw_hdr, 4) == 0) {
is_ivf = 1;
if (mem_get_le16(raw_hdr + 4) != 0) {
fprintf(stderr,
"Error: Unrecognized IVF version! This file may not"
" decode properly.");
}
input_ctx->fourcc = mem_get_le32(raw_hdr + 8);
input_ctx->width = mem_get_le16(raw_hdr + 12);
input_ctx->height = mem_get_le16(raw_hdr + 14);
input_ctx->framerate.numerator = mem_get_le32(raw_hdr + 16);
input_ctx->framerate.denominator = mem_get_le32(raw_hdr + 20);
fix_framerate(&input_ctx->framerate.numerator,
&input_ctx->framerate.denominator);
}
}
if (!is_ivf) {
rewind(input_ctx->file);
input_ctx->detect.buf_read = 0;
} else {
input_ctx->detect.position = 4;
}
return is_ivf;
}
int ivf_read_frame(FILE *infile, uint8_t **buffer, size_t *bytes_read,
size_t *buffer_size) {
char raw_header[IVF_FRAME_HDR_SZ] = { 0 };
size_t frame_size = 0;
if (fread(raw_header, IVF_FRAME_HDR_SZ, 1, infile) != 1) {
if (!feof(infile)) warn("Failed to read frame size");
} else {
frame_size = mem_get_le32(raw_header);
if (frame_size > 256 * 1024 * 1024) {
warn("Read invalid frame size (%u)", (unsigned int)frame_size);
frame_size = 0;
}
if (frame_size > *buffer_size) {
uint8_t *new_buffer = realloc(*buffer, 2 * frame_size);
if (new_buffer) {
*buffer = new_buffer;
*buffer_size = 2 * frame_size;
} else {
warn("Failed to allocate compressed data buffer");
frame_size = 0;
}
}
}
if (!feof(infile)) {
if (fread(*buffer, 1, frame_size, infile) != frame_size) {
warn("Failed to read full frame");
return 1;
}
*bytes_read = frame_size;
return 0;
}
return 1;
}