1/*
2 *  Copyright (c) 2013 The WebM project authors. All Rights Reserved.
3 *
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.
9 */
10#ifndef WEBMDEC_H_
11#define WEBMDEC_H_
12
13#include "./tools_common.h"
14
15#ifdef __cplusplus
16extern "C" {
17#endif
18
19struct VpxInputContext;
20
21struct WebmInputContext {
22  void *reader;
23  void *segment;
24  uint8_t *buffer;
25  const void *cluster;
26  const void *block_entry;
27  const void *block;
28  int block_frame_index;
29  int video_track_index;
30  uint64_t timestamp_ns;
31};
32
33// Checks if the input is a WebM file. If so, initializes WebMInputContext so
34// that webm_read_frame can be called to retrieve a video frame.
35// Returns 1 on success and 0 on failure or input is not WebM file.
36// TODO(vigneshv): Refactor this function into two smaller functions specific
37// to their task.
38int file_is_webm(struct WebmInputContext *webm_ctx,
39                 struct VpxInputContext *vpx_ctx);
40
41// Reads a WebM Video Frame. Memory for the buffer is created, owned and managed
42// by this function. For the first call, |buffer| should be NULL and
43// |*bytes_in_buffer| should be 0. Once all the frames are read and used,
44// webm_free() should be called, otherwise there will be a leak.
45// Parameters:
46//      webm_ctx - WebmInputContext object
47//      buffer - pointer where the frame data will be filled.
48//      bytes_in_buffer - pointer to buffer size.
49//      buffer_size - unused TODO(vigneshv): remove this
50// Return values:
51//      0 - Success
52//      1 - End of Stream
53//     -1 - Error
54// TODO(vigneshv): Make the return values consistent across all functions in
55// this file.
56int webm_read_frame(struct WebmInputContext *webm_ctx,
57                    uint8_t **buffer,
58                    size_t *bytes_in_buffer,
59                    size_t *buffer_size);
60
61// Guesses the frame rate of the input file based on the container timestamps.
62int webm_guess_framerate(struct WebmInputContext *webm_ctx,
63                         struct VpxInputContext *vpx_ctx);
64
65// Resets the WebMInputContext.
66void webm_free(struct WebmInputContext *webm_ctx);
67
68#ifdef __cplusplus
69}  // extern "C"
70#endif
71
72#endif  // WEBMDEC_H_
73