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 
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;
60 
61 static int probe(const AVProbeData *p)
62 {
63  int len, type, fps, w, h;
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 */
83 }
84 
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);
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);
125  st->codecpar->codec_tag = 0; /* no fourcc */
127  st->codecpar->channels = 1;
129  st->codecpar->sample_rate = 8000;
130  avpriv_set_pts_info(st, 64, 1, 8000); /* 8000 hz */
131  }
132 
133  mm->audio_pts = 0;
134  mm->video_pts = 0;
135  return 0;
136 }
137 
139  AVPacket *pkt)
140 {
141  MmDemuxContext *mm = s->priv_data;
142  AVIOContext *pb = s->pb;
143  unsigned char preamble[MM_PREAMBLE_SIZE];
144  unsigned int type, length;
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 (av_new_packet(pkt, length + MM_PREAMBLE_SIZE))
165  return AVERROR(ENOMEM);
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 (av_get_packet(s->pb, pkt, length)<0)
178  return AVERROR(ENOMEM);
179  pkt->stream_index = 1;
180  pkt->pts = mm->audio_pts++;
181  return 0;
182 
183  default :
184  av_log(s, AV_LOG_INFO, "unknown chunk type 0x%x\n", type);
185  avio_skip(pb, length);
186  }
187  }
188 }
189 
191  .name = "mm",
192  .long_name = NULL_IF_CONFIG_SMALL("American Laser Games MM"),
193  .priv_data_size = sizeof(MmDemuxContext),
194  .read_probe = probe,
197 };
#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
#define MM_PREAMBLE_SIZE
Definition: mm.c:39
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:4929
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3970
int size
Definition: avcodec.h:1483
GLint GLenum type
Definition: opengl_enc.c:104
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:334
AVInputFormat ff_mm_demuxer
Definition: mm.c:190
static AVPacket pkt
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:87
Format I/O context.
Definition: avformat.h:1358
static int read_header(AVFormatContext *s)
Definition: mm.c:85
#define MM_TYPE_AUDIO
Definition: mm.c:48
int width
Video only.
Definition: avcodec.h:4036
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4502
#define height
uint8_t * data
Definition: avcodec.h:1482
#define MM_TYPE_INTRA_HHV
Definition: mm.c:46
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:310
uint64_t channel_layout
Audio only.
Definition: avcodec.h:4072
#define av_log(a,...)
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:650
static int probe(const AVProbeData *p)
Definition: mm.c:61
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:86
#define MM_HEADER_LEN_V
Definition: mm.c:51
#define MM_TYPE_INTER_HHV
Definition: mm.c:47
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:772
unsigned int video_pts
Definition: mm.c:58
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
#define MM_HEADER_LEN_AV
Definition: mm.c:52
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3966
GLsizei GLsizei * length
Definition: opengl_enc.c:114
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:449
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
#define MM_TYPE_INTRA_HH
Definition: mm.c:44
static int read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: mm.c:138
audio channel layout utility functions
unsigned int audio_pts
Definition: mm.c:58
#define width
uint8_t w
Definition: llviddspenc.c:38
#define s(width, name)
Definition: cbs_vp9.c:257
Stream structure.
Definition: avformat.h:881
#define AV_LOG_INFO
Standard information.
Definition: log.h:187
AVIOContext * pb
I/O context.
Definition: avformat.h:1400
#define MM_TYPE_INTRA
Definition: mm.c:43
#define MM_TYPE_HEADER
Definition: mm.c:41
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:456
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
int sample_rate
Audio only.
Definition: avcodec.h:4080
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:756
Main libavformat public API header.
#define MM_TYPE_INTER
Definition: mm.c:42
#define MM_TYPE_PALETTE
Definition: mm.c:49
int len
#define MM_TYPE_INTER_HH
Definition: mm.c:45
void * priv_data
Format private data.
Definition: avformat.h:1386
int channels
Audio only.
Definition: avcodec.h:4076
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:1028
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: avcodec.h:3974
int stream_index
Definition: avcodec.h:1484
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
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
This structure stores compressed data.
Definition: avcodec.h:1459
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1475