bmv.c
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1 /*
2  * Discworld II BMV demuxer
3  * Copyright (c) 2011 Konstantin Shishkov.
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
23 #include "avformat.h"
24 #include "internal.h"
25 
26 enum BMVFlags {
27  BMV_NOP = 0,
31 
32  BMV_AUDIO = 0x20,
33 };
34 
35 typedef struct BMVContext {
37  int size;
38  int get_next;
39  int64_t audio_pos;
40 } BMVContext;
41 
43 {
44  AVStream *st, *ast;
45  BMVContext *c = s->priv_data;
46 
47  st = avformat_new_stream(s, 0);
48  if (!st)
49  return AVERROR(ENOMEM);
52  st->codec->width = 640;
53  st->codec->height = 429;
55  avpriv_set_pts_info(st, 16, 1, 12);
56  ast = avformat_new_stream(s, 0);
57  if (!ast)
58  return AVERROR(ENOMEM);
61  ast->codec->channels = 2;
63  ast->codec->sample_rate = 22050;
64  avpriv_set_pts_info(ast, 16, 1, 22050);
65 
66  c->get_next = 1;
67  c->audio_pos = 0;
68  return 0;
69 }
70 
72 {
73  BMVContext *c = s->priv_data;
74  int type;
75  void *tmp;
76 
77  while (c->get_next) {
78  if (s->pb->eof_reached)
79  return AVERROR_EOF;
80  type = avio_r8(s->pb);
81  if (type == BMV_NOP)
82  continue;
83  if (type == BMV_END)
84  return AVERROR_EOF;
85  c->size = avio_rl24(s->pb);
86  if (!c->size)
87  return AVERROR_INVALIDDATA;
88  tmp = av_realloc(c->packet, c->size + 1);
89  if (!tmp)
90  return AVERROR(ENOMEM);
91  c->packet = tmp;
92  c->packet[0] = type;
93  if (avio_read(s->pb, c->packet + 1, c->size) != c->size)
94  return AVERROR(EIO);
95  if (type & BMV_AUDIO) {
96  int audio_size = c->packet[1] * 65 + 1;
97  if (audio_size >= c->size) {
98  av_log(s, AV_LOG_ERROR, "Reported audio size %d is bigger than packet size (%d)\n",
99  audio_size, c->size);
100  return AVERROR_INVALIDDATA;
101  }
102  if (av_new_packet(pkt, audio_size) < 0)
103  return AVERROR(ENOMEM);
104  memcpy(pkt->data, c->packet + 1, pkt->size);
105  pkt->stream_index = 1;
106  pkt->pts = c->audio_pos;
107  pkt->duration = c->packet[1] * 32;
108  c->audio_pos += pkt->duration;
109  c->get_next = 0;
110  return pkt->size;
111  } else
112  break;
113  }
114  if (av_new_packet(pkt, c->size + 1) < 0)
115  return AVERROR(ENOMEM);
116  pkt->stream_index = 0;
117  c->get_next = 1;
118  memcpy(pkt->data, c->packet, pkt->size);
119  return pkt->size;
120 }
121 
123 {
124  BMVContext *c = s->priv_data;
125 
126  av_freep(&c->packet);
127 
128  return 0;
129 }
130 
132  .name = "bmv",
133  .long_name = NULL_IF_CONFIG_SMALL("Discworld II BMV"),
134  .priv_data_size = sizeof(BMVContext),
138  .extensions = "bmv",
139 };
AVInputFormat ff_bmv_demuxer
Definition: bmv.c:131
Definition: bmv.c:28
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:3283
Definition: bmv.c:30
int size
Definition: avcodec.h:916
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1533
#define AV_CH_LAYOUT_STEREO
uint8_t * packet
Definition: bmv.c:36
void av_freep(void *arg)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc() and set the pointer ...
Definition: mem.c:151
Format I/O context.
Definition: avformat.h:828
int get_next
Definition: bmv.c:38
uint8_t
8 bit with PIX_FMT_RGB32 palette
Definition: pixfmt.h:76
uint8_t * data
Definition: avcodec.h:915
Definition: bmv.c:31
static av_cold int read_close(AVFormatContext *ctx)
Definition: libcdio.c:145
int duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: avcodec.h:937
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:446
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:56
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:88
static int bmv_read_header(AVFormatContext *s)
Definition: bmv.c:42
int64_t audio_pos
Definition: bmv.c:39
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:146
AVStream * avformat_new_stream(AVFormatContext *s, AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:2736
uint64_t channel_layout
Audio channel layout.
Definition: avcodec.h:2165
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:437
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:641
static int64_t audio_size
Definition: avconv.c:88
audio channel layout utility functions
static int bmv_read_close(AVFormatContext *s)
Definition: bmv.c:122
int width
picture width / height.
Definition: avcodec.h:1508
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:536
Definition: bmv.c:29
Stream structure.
Definition: avformat.h:622
enum AVMediaType codec_type
Definition: avcodec.h:1347
enum AVCodecID codec_id
Definition: avcodec.h:1350
int sample_rate
samples per second
Definition: avcodec.h:2104
AVIOContext * pb
I/O context.
Definition: avformat.h:861
static int read_packet(AVFormatContext *ctx, AVPacket *pkt)
Definition: libcdio.c:114
Definition: bmv.c:35
BMVFlags
Definition: bmv.c:27
int size
Definition: bmv.c:37
Main libavformat public API header.
void * av_realloc(void *ptr, size_t size)
Allocate or reallocate a block of memory.
Definition: mem.c:116
int eof_reached
true if eof reached
Definition: avio.h:96
int channels
number of audio channels
Definition: avcodec.h:2105
static int bmv_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: bmv.c:71
void * priv_data
Format private data.
Definition: avformat.h:848
Definition: bmv.c:36
struct BMVContext BMVContext
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:455
unsigned int avio_rl24(AVIOContext *s)
Definition: aviobuf.c:538
int stream_index
Definition: avcodec.h:917
This structure stores compressed data.
Definition: avcodec.h:898
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:908