aom/webmdec.h

73 строки
2.3 KiB
C

/*
* 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.
*/
#ifndef WEBMDEC_H_
#define WEBMDEC_H_
#include "./tools_common.h"
#ifdef __cplusplus
extern "C" {
#endif
struct VpxInputContext;
struct WebmInputContext {
void *reader;
void *segment;
uint8_t *buffer;
const void *cluster;
const void *block_entry;
const void *block;
int block_frame_index;
int video_track_index;
uint64_t timestamp_ns;
};
// Checks if the input is a WebM file. If so, initializes WebMInputContext so
// that webm_read_frame can be called to retrieve a video frame.
// Returns 1 on success and 0 on failure or input is not WebM file.
// TODO(vigneshv): Refactor this function into two smaller functions specific
// to their task.
int file_is_webm(struct WebmInputContext *webm_ctx,
struct VpxInputContext *vpx_ctx);
// Reads a WebM Video Frame. Memory for the buffer is created, owned and managed
// by this function. For the first call, |buffer| should be NULL and
// |*bytes_in_buffer| should be 0. Once all the frames are read and used,
// webm_free() should be called, otherwise there will be a leak.
// Parameters:
// webm_ctx - WebmInputContext object
// buffer - pointer where the frame data will be filled.
// bytes_in_buffer - pointer to buffer size.
// buffer_size - unused TODO(vigneshv): remove this
// Return values:
// 0 - Success
// 1 - End of Stream
// -1 - Error
// TODO(vigneshv): Make the return values consistent across all functions in
// this file.
int webm_read_frame(struct WebmInputContext *webm_ctx,
uint8_t **buffer,
size_t *bytes_in_buffer,
size_t *buffer_size);
// Guesses the frame rate of the input file based on the container timestamps.
int webm_guess_framerate(struct WebmInputContext *webm_ctx,
struct VpxInputContext *vpx_ctx);
// Resets the WebMInputContext.
void webm_free(struct WebmInputContext *webm_ctx);
#ifdef __cplusplus
} // extern "C"
#endif
#endif // WEBMDEC_H_