FFmpeg
mvi.c
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1 /*
2  * Motion Pixels MVI Demuxer
3  * Copyright (c) 2008 Gregory Montoir (cyx@users.sourceforge.net)
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include <inttypes.h>
23 
25 #include "avformat.h"
26 #include "internal.h"
27 
28 #define MVI_FRAC_BITS 10
29 
30 #define MVI_AUDIO_STREAM_INDEX 0
31 #define MVI_VIDEO_STREAM_INDEX 1
32 
33 typedef struct MviDemuxContext {
34  unsigned int (*get_int)(AVIOContext *);
35  uint32_t audio_data_size;
37  uint64_t audio_frame_size;
41 
43 {
44  MviDemuxContext *mvi = s->priv_data;
45  AVIOContext *pb = s->pb;
46  AVStream *ast, *vst;
47  unsigned int version, frames_count, msecs_per_frame, player_version;
48  int ret;
49 
50  ast = avformat_new_stream(s, NULL);
51  if (!ast)
52  return AVERROR(ENOMEM);
53 
54  vst = avformat_new_stream(s, NULL);
55  if (!vst)
56  return AVERROR(ENOMEM);
57 
58  if ((ret = ff_alloc_extradata(vst->codecpar, 2)) < 0)
59  return ret;
60 
61  version = avio_r8(pb);
62  vst->codecpar->extradata[0] = avio_r8(pb);
63  vst->codecpar->extradata[1] = avio_r8(pb);
64  frames_count = avio_rl32(pb);
65  msecs_per_frame = avio_rl32(pb);
66  vst->codecpar->width = avio_rl16(pb);
67  vst->codecpar->height = avio_rl16(pb);
68  avio_r8(pb);
69  ast->codecpar->sample_rate = avio_rl16(pb);
70  mvi->audio_data_size = avio_rl32(pb);
71  avio_r8(pb);
72  player_version = avio_rl32(pb);
73  avio_rl16(pb);
74  avio_r8(pb);
75 
76  if (frames_count == 0 || mvi->audio_data_size == 0)
77  return AVERROR_INVALIDDATA;
78 
79  if (version != 7 || player_version > 213) {
80  av_log(s, AV_LOG_ERROR, "unhandled version (%d,%d)\n", version, player_version);
81  return AVERROR_INVALIDDATA;
82  }
83 
84  avpriv_set_pts_info(ast, 64, 1, ast->codecpar->sample_rate);
87  ast->codecpar->channels = 1;
90  ast->codecpar->bit_rate = ast->codecpar->sample_rate * 8;
91 
92  avpriv_set_pts_info(vst, 64, msecs_per_frame, 1000000);
93  vst->avg_frame_rate = av_inv_q(vst->time_base);
96 
97  mvi->get_int = (vst->codecpar->width * vst->codecpar->height < (1 << 16)) ? avio_rl16 : avio_rl24;
98 
99  mvi->audio_frame_size = ((uint64_t)mvi->audio_data_size << MVI_FRAC_BITS) / frames_count;
100  if (mvi->audio_frame_size <= 1 << MVI_FRAC_BITS - 1) {
101  av_log(s, AV_LOG_ERROR,
102  "Invalid audio_data_size (%"PRIu32") or frames_count (%u)\n",
103  mvi->audio_data_size, frames_count);
104  return AVERROR_INVALIDDATA;
105  }
106 
107  mvi->audio_size_counter = (ast->codecpar->sample_rate * 830 / mvi->audio_frame_size - 1) * mvi->audio_frame_size;
108  mvi->audio_size_left = mvi->audio_data_size;
109 
110  return 0;
111 }
112 
114 {
115  int ret, count;
116  MviDemuxContext *mvi = s->priv_data;
117  AVIOContext *pb = s->pb;
118 
119  if (mvi->video_frame_size == 0) {
120  mvi->video_frame_size = (mvi->get_int)(pb);
121  if (mvi->audio_size_left == 0)
122  return AVERROR(EIO);
123  count = (mvi->audio_size_counter + mvi->audio_frame_size + 512) >> MVI_FRAC_BITS;
124  if (count > mvi->audio_size_left)
125  count = mvi->audio_size_left;
126  if ((ret = av_get_packet(pb, pkt, count)) < 0)
127  return ret;
129  mvi->audio_size_left -= count;
130  mvi->audio_size_counter += mvi->audio_frame_size - (count << MVI_FRAC_BITS);
131  } else {
132  if ((ret = av_get_packet(pb, pkt, mvi->video_frame_size)) < 0)
133  return ret;
135  mvi->video_frame_size = 0;
136  }
137  return 0;
138 }
139 
141  .name = "mvi",
142  .long_name = NULL_IF_CONFIG_SMALL("Motion Pixels MVI"),
143  .priv_data_size = sizeof(MviDemuxContext),
146  .extensions = "mvi",
147 };
#define NULL
Definition: coverity.c:32
Bytestream IO Context.
Definition: avio.h:161
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
AVInputFormat ff_mvi_demuxer
Definition: mvi.c:140
#define MVI_AUDIO_STREAM_INDEX
Definition: mvi.c:30
void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: utils.c:4928
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3981
int version
Definition: avisynth_c.h:858
static AVPacket pkt
Format I/O context.
Definition: avformat.h:1357
int width
Video only.
Definition: avcodec.h:4047
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4501
int av_get_packet(AVIOContext *s, AVPacket *pkt, int size)
Allocate and read the payload of a packet and initialize its fields with default values.
Definition: utils.c:308
uint64_t channel_layout
Audio only.
Definition: avcodec.h:4083
#define av_log(a,...)
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: avcodec.h:4010
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:772
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3977
unsigned int(* get_int)(AVIOContext *)
Definition: mvi.c:34
GLsizei count
Definition: opengl_enc.c:108
AVRational avg_frame_rate
Average framerate.
Definition: avformat.h:953
int audio_size_left
Definition: mvi.c:38
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:641
audio channel layout utility functions
int ff_alloc_extradata(AVCodecParameters *par, int size)
Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end which is always set to 0...
Definition: utils.c:3320
uint64_t audio_size_counter
Definition: mvi.c:36
#define s(width, name)
Definition: cbs_vp9.c:257
#define MVI_VIDEO_STREAM_INDEX
Definition: mvi.c:31
Stream structure.
Definition: avformat.h:880
uint64_t audio_frame_size
Definition: mvi.c:37
AVIOContext * pb
I/O context.
Definition: avformat.h:1399
uint32_t audio_data_size
Definition: mvi.c:35
int video_frame_size
Definition: mvi.c:39
static av_always_inline AVRational av_inv_q(AVRational q)
Invert a rational.
Definition: rational.h:159
int sample_rate
Audio only.
Definition: avcodec.h:4091
static int read_header(AVFormatContext *s)
Definition: mvi.c:42
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:756
Main libavformat public API header.
int
#define MVI_FRAC_BITS
Definition: mvi.c:28
void * priv_data
Format private data.
Definition: avformat.h:1385
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: avcodec.h:4023
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: avcodec.h:3995
int channels
Audio only.
Definition: avcodec.h:4087
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:654
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1027
unsigned int avio_rl24(AVIOContext *s)
Definition: aviobuf.c:764
int stream_index
Definition: avcodec.h:1495
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avformat.h:909
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
#define AV_CH_LAYOUT_MONO
This structure stores compressed data.
Definition: avcodec.h:1470
static int read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: mvi.c:113