FFmpeg
gdv.c
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1 /*
2  * Gremlin Digital Video demuxer
3  * Copyright (c) 2017 Paul B Mahol
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 "libavutil/intreadwrite.h"
23 
24 #include "avformat.h"
25 #include "avio.h"
26 #include "internal.h"
27 
28 typedef struct GDVContext {
30  int is_audio;
34  unsigned pal[256];
35 } GDVContext;
36 
37 static int gdv_read_probe(const AVProbeData *p)
38 {
39  if (AV_RL32(p->buf) == 0x29111994)
40  return AVPROBE_SCORE_MAX;
41 
42  return 0;
43 }
44 
45 static struct {
46  uint16_t id;
47  uint16_t width;
48  uint16_t height;
49 } FixedSize[] = {
50  { 0, 320, 200},
51  { 1, 640, 200},
52  { 2, 320, 167},
53  { 3, 320, 180},
54  { 4, 320, 400},
55  { 5, 320, 170},
56  { 6, 160, 85},
57  { 7, 160, 83},
58  { 8, 160, 90},
59  { 9, 280, 128},
60  {10, 320, 240},
61  {11, 320, 201},
62  {16, 640, 400},
63  {17, 640, 200},
64  {18, 640, 180},
65  {19, 640, 167},
66  {20, 640, 170},
67  {21, 320, 240}
68 };
69 
71 {
72  GDVContext *gdv = ctx->priv_data;
73  AVIOContext *pb = ctx->pb;
74  AVStream *vst, *ast;
75  unsigned fps, snd_flags, vid_depth, size_id;
76 
77  avio_skip(pb, 4);
78  size_id = avio_rl16(pb);
79 
80  vst = avformat_new_stream(ctx, 0);
81  if (!vst)
82  return AVERROR(ENOMEM);
83 
84  vst->start_time = 0;
85  vst->duration =
86  vst->nb_frames = avio_rl16(pb);
87 
88  fps = avio_rl16(pb);
89  if (!fps)
90  return AVERROR_INVALIDDATA;
91 
92  snd_flags = avio_rl16(pb);
93  if (snd_flags & 1) {
94  ast = avformat_new_stream(ctx, 0);
95  if (!ast)
96  return AVERROR(ENOMEM);
97 
98  ast->start_time = 0;
100  ast->codecpar->codec_tag = 0;
101  ast->codecpar->sample_rate = avio_rl16(pb);
102  ast->codecpar->ch_layout.nb_channels = 1 + !!(snd_flags & 2);
103  if (snd_flags & 8) {
105  } else {
106  ast->codecpar->codec_id = (snd_flags & 4) ? AV_CODEC_ID_PCM_S16LE : AV_CODEC_ID_PCM_U8;
107  }
108 
109  avpriv_set_pts_info(ast, 64, 1, ast->codecpar->sample_rate);
110  gdv->audio_size = (ast->codecpar->sample_rate / fps) *
112  (1 + !!(snd_flags & 4)) / (1 + !!(snd_flags & 8));
113  gdv->is_audio = 1;
114  } else {
115  avio_skip(pb, 2);
116  }
117  vid_depth = avio_rl16(pb);
118  avio_skip(pb, 4);
119 
122  vst->codecpar->codec_tag = 0;
123  vst->codecpar->width = avio_rl16(pb);
124  vst->codecpar->height = avio_rl16(pb);
125 
126  if (vst->codecpar->width == 0 || vst->codecpar->height == 0) {
127  int i;
128 
129  for (i = 0; i < FF_ARRAY_ELEMS(FixedSize) - 1; i++) {
130  if (FixedSize[i].id == size_id)
131  break;
132  }
133 
134  vst->codecpar->width = FixedSize[i].width;
135  vst->codecpar->height = FixedSize[i].height;
136  }
137 
138  avpriv_set_pts_info(vst, 64, 1, fps);
139 
140  if (vid_depth & 1) {
141  int i;
142 
143  for (i = 0; i < 256; i++) {
144  unsigned r = avio_r8(pb);
145  unsigned g = avio_r8(pb);
146  unsigned b = avio_r8(pb);
147  gdv->pal[i] = 0xFFU << 24 | r << 18 | g << 10 | b << 2;
148  }
149  }
150 
151  gdv->is_first_video = 1;
152 
153  return 0;
154 }
155 
157 {
158  GDVContext *gdv = ctx->priv_data;
159  AVIOContext *pb = ctx->pb;
160  int ret;
161 
162  if (avio_feof(pb))
163  return pb->error ? pb->error : AVERROR_EOF;
164 
165  if (gdv->audio_size && gdv->is_audio) {
166  ret = av_get_packet(pb, pkt, gdv->audio_size);
167  if (ret < 0)
168  return ret;
169  pkt->stream_index = 1;
170  gdv->is_audio = 0;
171  } else {
172  uint8_t *pal;
173 
174  if (avio_rl16(pb) != 0x1305)
175  return AVERROR_INVALIDDATA;
176  ret = av_get_packet(pb, pkt, 4 + avio_rl16(pb));
177  if (ret < 0)
178  return ret;
179  pkt->stream_index = 0;
180  gdv->is_audio = 1;
181 
182  if (gdv->is_first_video) {
185  if (!pal) {
186  return AVERROR(ENOMEM);
187  }
188  memcpy(pal, gdv->pal, AVPALETTE_SIZE);
190  gdv->is_first_video = 0;
191  }
192  }
193 
194  return 0;
195 }
196 
198  .name = "gdv",
199  .long_name = NULL_IF_CONFIG_SMALL("Gremlin Digital Video"),
200  .priv_data_size = sizeof(GDVContext),
204 };
AV_CODEC_ID_PCM_S16LE
@ AV_CODEC_ID_PCM_S16LE
Definition: codec_id.h:320
r
const char * r
Definition: vf_curves.c:116
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
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
b
#define b
Definition: input.c:34
AV_PKT_DATA_PALETTE
@ AV_PKT_DATA_PALETTE
An AV_PKT_DATA_PALETTE side data packet contains exactly AVPALETTE_SIZE bytes worth of palette.
Definition: packet.h:47
AVIOContext::error
int error
contains the error code or 0 if no error happened
Definition: avio.h:241
AV_CODEC_ID_GDV
@ AV_CODEC_ID_GDV
Definition: codec_id.h:284
AVCodecParameters::codec_tag
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: codec_par.h:65
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:300
AV_PKT_FLAG_KEY
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:429
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:465
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
AVStream::duration
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:998
avio_rl16
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:743
pkt
AVPacket * pkt
Definition: movenc.c:59
AVInputFormat
Definition: avformat.h:656
FF_ARRAY_ELEMS
#define FF_ARRAY_ELEMS(a)
Definition: sinewin_tablegen.c:29
gdv_read_probe
static int gdv_read_probe(const AVProbeData *p)
Definition: gdv.c:37
intreadwrite.h
id
uint16_t id
Definition: gdv.c:46
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:661
g
const char * g
Definition: vf_curves.c:117
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
GDVContext::audio_size
int audio_size
Definition: gdv.c:31
ctx
AVFormatContext * ctx
Definition: movenc.c:48
FixedSize
static struct @263 FixedSize[]
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
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:532
GDVContext::is_audio
int is_audio
Definition: gdv.c:30
read_probe
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
AVPALETTE_SIZE
#define AVPALETTE_SIZE
Definition: pixfmt.h:32
AVFormatContext::pb
AVIOContext * pb
I/O context.
Definition: avformat.h:1255
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:453
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:212
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:177
AVStream::nb_frames
int64_t nb_frames
number of frames in this stream if known or 0
Definition: avformat.h:1000
GDVContext::audio_stream_index
int audio_stream_index
Definition: gdv.c:32
AVIOContext
Bytestream IO Context.
Definition: avio.h:162
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
GDVContext::is_first_video
int is_first_video
Definition: gdv.c:29
ff_gdv_demuxer
const AVInputFormat ff_gdv_demuxer
Definition: gdv.c:197
avio.h
gdv_read_header
static int gdv_read_header(AVFormatContext *ctx)
Definition: gdv.c:70
GDVContext
Definition: gdv.c:30
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:632
AVPacket::flags
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:380
height
uint16_t height
Definition: gdv.c:48
width
uint16_t width
Definition: gdv.c:47
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
AVCodecParameters::height
int height
Definition: codec_par.h:128
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
GDVContext::pal
uint32_t pal[256]
Definition: gdv.c:37
ret
ret
Definition: filter_design.txt:187
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
AVStream
Stream structure.
Definition: avformat.h:948
avformat.h
GDVContext::video_stream_index
int video_stream_index
Definition: gdv.c:33
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:92
U
#define U(x)
Definition: vpx_arith.h:37
av_packet_new_side_data
uint8_t * av_packet_new_side_data(AVPacket *pkt, enum AVPacketSideDataType type, size_t size)
Allocate new information of a packet.
Definition: avpacket.c:230
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
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
AV_CODEC_ID_PCM_U8
@ AV_CODEC_ID_PCM_U8
Definition: codec_id.h:325
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
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
AVStream::start_time
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base.
Definition: avformat.h:988
AVFormatContext::priv_data
void * priv_data
Format private data.
Definition: avformat.h:1241
AV_CODEC_ID_GREMLIN_DPCM
@ AV_CODEC_ID_GREMLIN_DPCM
Definition: codec_id.h:425
gdv_read_packet
static int gdv_read_packet(AVFormatContext *ctx, AVPacket *pkt)
Definition: gdv.c:156
avio_feof
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:375