FFmpeg: libavformat/mm.c Source File

FFmpeg
mm.c
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1 /*
2  * American Laser Games MM Format Demuxer
3  * Copyright (c) 2006 Peter Ross
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 /**
23  * @file
24  * American Laser Games MM Format Demuxer
25  * by Peter Ross (pross@xvid.org)
26  *
27  * The MM format was used by IBM-PC ports of ALG's "arcade shooter" games,
28  * including Mad Dog McCree and Crime Patrol.
29  *
30  * Technical details here:
31  * http://wiki.multimedia.cx/index.php?title=American_Laser_Games_MM
32  */
33 
34 #include "libavutil/channel_layout.h"
35 #include "libavutil/intreadwrite.h"
36 #include "avformat.h"
37 #include "internal.h"
38 
39  #define MM_PREAMBLE_SIZE 6
40 
41  #define MM_TYPE_HEADER 0x0
42  #define MM_TYPE_INTER 0x5
43  #define MM_TYPE_INTRA 0x8
44  #define MM_TYPE_INTRA_HH 0xc
45  #define MM_TYPE_INTER_HH 0xd
46  #define MM_TYPE_INTRA_HHV 0xe
47  #define MM_TYPE_INTER_HHV 0xf
48  #define MM_TYPE_AUDIO 0x15
49  #define MM_TYPE_PALETTE 0x31
50 
51  #define MM_HEADER_LEN_V 0x16 /* video only */
52  #define MM_HEADER_LEN_AV 0x18 /* video + audio */
53 
54  #define MM_PALETTE_COUNT 128
55  #define MM_PALETTE_SIZE (MM_PALETTE_COUNT*3)
56 
57  typedef struct MmDemuxContext {
58   unsigned int audio_pts, video_pts;
59 } MmDemuxContext;
60 
61  static int probe(const AVProbeData *p)
62 {
63  int len, type, fps, w, h;
64  if (p->buf_size < MM_HEADER_LEN_AV + MM_PREAMBLE_SIZE)
65  return 0;
66  /* the first chunk is always the header */
67  if (AV_RL16(&p->buf[0]) != MM_TYPE_HEADER)
68  return 0;
69  len = AV_RL32(&p->buf[2]);
70  if (len != MM_HEADER_LEN_V && len != MM_HEADER_LEN_AV)
71  return 0;
72  fps = AV_RL16(&p->buf[8]);
73  w = AV_RL16(&p->buf[12]);
74  h = AV_RL16(&p->buf[14]);
75  if (!fps || fps > 60 || !w || w > 2048 || !h || h > 2048)
76  return 0;
77  type = AV_RL16(&p->buf[len]);
78  if (!type || type > 0x31)
79  return 0;
80 
81  /* only return half certainty since this check is a bit sketchy */
82  return AVPROBE_SCORE_EXTENSION;
83 }
84 
85  static int read_header(AVFormatContext *s)
86 {
87  MmDemuxContext *mm = s->priv_data;
88  AVIOContext *pb = s->pb;
89  AVStream *st;
90 
91  unsigned int type, length;
92  unsigned int frame_rate, width, height;
93 
94  type = avio_rl16(pb);
95  length = avio_rl32(pb);
96 
97  if (type != MM_TYPE_HEADER)
98  return AVERROR_INVALIDDATA;
99 
100  /* read header */
101  avio_rl16(pb); /* total number of chunks */
102  frame_rate = avio_rl16(pb);
103  avio_rl16(pb); /* ibm-pc video bios mode */
104  width = avio_rl16(pb);
105  height = avio_rl16(pb);
106  avio_skip(pb, length - 10); /* unknown data */
107 
108  /* video stream */
109  st = avformat_new_stream(s, NULL);
110  if (!st)
111  return AVERROR(ENOMEM);
112  st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
113  st->codecpar->codec_id = AV_CODEC_ID_MMVIDEO;
114  st->codecpar->codec_tag = 0; /* no fourcc */
115  st->codecpar->width = width;
116  st->codecpar->height = height;
117  avpriv_set_pts_info(st, 64, 1, frame_rate);
118 
119  /* audio stream */
120  if (length == MM_HEADER_LEN_AV) {
121  st = avformat_new_stream(s, NULL);
122  if (!st)
123  return AVERROR(ENOMEM);
124  st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
125  st->codecpar->codec_tag = 0; /* no fourcc */
126  st->codecpar->codec_id = AV_CODEC_ID_PCM_U8;
127  st->codecpar->ch_layout = (AVChannelLayout)AV_CHANNEL_LAYOUT_MONO;
128  st->codecpar->sample_rate = 8000;
129  avpriv_set_pts_info(st, 64, 1, 8000); /* 8000 hz */
130  }
131 
132  mm->audio_pts = 0;
133  mm->video_pts = 0;
134  return 0;
135 }
136 
137  static int read_packet(AVFormatContext *s,
138  AVPacket *pkt)
139 {
140  MmDemuxContext *mm = s->priv_data;
141  AVIOContext *pb = s->pb;
142  unsigned char preamble[MM_PREAMBLE_SIZE];
143  unsigned int type, length;
144  int ret;
145 
146  while(1) {
147 
148  if (avio_read(pb, preamble, MM_PREAMBLE_SIZE) != MM_PREAMBLE_SIZE) {
149  return AVERROR(EIO);
150  }
151 
152  type = AV_RL16(&preamble[0]);
153  length = AV_RL16(&preamble[2]);
154 
155  switch(type) {
156  case MM_TYPE_PALETTE :
157  case MM_TYPE_INTER :
158  case MM_TYPE_INTRA :
159  case MM_TYPE_INTRA_HH :
160  case MM_TYPE_INTER_HH :
161  case MM_TYPE_INTRA_HHV :
162  case MM_TYPE_INTER_HHV :
163  /* output preamble + data */
164  if ((ret = av_new_packet(pkt, length + MM_PREAMBLE_SIZE)) < 0)
165  return ret;
166  memcpy(pkt->data, preamble, MM_PREAMBLE_SIZE);
167  if (avio_read(pb, pkt->data + MM_PREAMBLE_SIZE, length) != length)
168  return AVERROR(EIO);
169  pkt->size = length + MM_PREAMBLE_SIZE;
170  pkt->stream_index = 0;
171  pkt->pts = mm->video_pts;
172  if (type!=MM_TYPE_PALETTE)
173  mm->video_pts++;
174  return 0;
175 
176  case MM_TYPE_AUDIO :
177  if (s->nb_streams < 2)
178  return AVERROR_INVALIDDATA;
179  if ((ret = av_get_packet(s->pb, pkt, length)) < 0)
180  return ret;
181  pkt->stream_index = 1;
182  pkt->pts = mm->audio_pts++;
183  return 0;
184 
185  default :
186  av_log(s, AV_LOG_INFO, "unknown chunk type 0x%x\n", type);
187  avio_skip(pb, length);
188  }
189  }
190 }
191 
192  const AVInputFormat ff_mm_demuxer = {
193  .name = "mm",
194  .long_name = NULL_IF_CONFIG_SMALL("American Laser Games MM"),
195  .priv_data_size = sizeof(MmDemuxContext),
196  .read_probe = probe,
197  .read_header = read_header,
198  .read_packet = read_packet,
199 };
ff_mm_demuxer
const AVInputFormat ff_mm_demuxer
Definition: mm.c:192
AVERROR
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
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: options.c:237
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:57
MmDemuxContext::video_pts
unsigned int video_pts
Definition: mm.c:58
read_packet
static int read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: mm.c:137
MM_TYPE_INTER_HHV
#define MM_TYPE_INTER_HHV
Definition: mm.c:47
MM_TYPE_INTER
#define MM_TYPE_INTER
Definition: mm.c:42
w
uint8_t w
Definition: llviddspenc.c:38
AVPacket::data
uint8_t * data
Definition: packet.h:374
AV_CHANNEL_LAYOUT_MONO
#define AV_CHANNEL_LAYOUT_MONO
Definition: channel_layout.h:353
AVCodecParameters::codec_tag
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: codec_par.h:65
AVProbeData::buf_size
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:456
avpriv_set_pts_info
void avpriv_set_pts_info(AVStream *st, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: avformat.c:697
type
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf type
Definition: writing_filters.txt:86
avio_rl16
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:743
MM_TYPE_INTRA_HHV
#define MM_TYPE_INTRA_HHV
Definition: mm.c:46
pkt
AVPacket * pkt
Definition: movenc.c:59
AVInputFormat
Definition: avformat.h:656
MM_TYPE_INTRA_HH
#define MM_TYPE_INTRA_HH
Definition: mm.c:44
width
#define width
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:256
av_new_packet
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:97
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:661
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:455
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
AVCodecParameters::width
int width
Video only.
Definition: codec_par.h:127
AV_RL16
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:94
MM_TYPE_HEADER
#define MM_TYPE_HEADER
Definition: mm.c:41
probe
static int probe(const AVProbeData *p)
Definition: mm.c:61
AVFormatContext
Format I/O context.
Definition: avformat.h:1213
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1108
NULL
#define NULL
Definition: coverity.c:32
read_probe
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:453
MM_PREAMBLE_SIZE
#define MM_PREAMBLE_SIZE
Definition: mm.c:39
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:212
AVPROBE_SCORE_EXTENSION
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:463
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:177
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:759
AVIOContext
Bytestream IO Context.
Definition: avio.h:162
MmDemuxContext::audio_pts
unsigned int audio_pts
Definition: mm.c:58
AVPacket::size
int size
Definition: packet.h:375
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:290
height
#define height
AV_CODEC_ID_MMVIDEO
@ AV_CODEC_ID_MMVIDEO
Definition: codec_id.h:130
AV_LOG_INFO
#define AV_LOG_INFO
Standard information.
Definition: log.h:191
MM_TYPE_PALETTE
#define MM_TYPE_PALETTE
Definition: mm.c:49
MM_HEADER_LEN_AV
#define MM_HEADER_LEN_AV
Definition: mm.c:52
AVPacket::pts
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:367
AVCodecParameters::height
int height
Definition: codec_par.h:128
MM_TYPE_INTER_HH
#define MM_TYPE_INTER_HH
Definition: mm.c:45
len
int len
Definition: vorbis_enc_data.h:426
av_get_packet
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:102
MmDemuxContext
Definition: mm.c:57
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:948
avformat.h
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:92
channel_layout.h
MM_TYPE_INTRA
#define MM_TYPE_INTRA
Definition: mm.c:43
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:641
AVPacket::stream_index
int stream_index
Definition: packet.h:376
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:347
MM_TYPE_AUDIO
#define MM_TYPE_AUDIO
Definition: mm.c:48
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
AV_CODEC_ID_PCM_U8
@ AV_CODEC_ID_PCM_U8
Definition: codec_id.h:323
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:61
AVPacket
This structure stores compressed data.
Definition: packet.h:351
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
MM_HEADER_LEN_V
#define MM_HEADER_LEN_V
Definition: mm.c:51
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
h
h
Definition: vp9dsp_template.c:2038
read_header
static int read_header(AVFormatContext *s)
Definition: mm.c:85
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