FFmpeg  4.4.4
frmdec.c
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1 /*
2  * Megalux Frame demuxer
3  * Copyright (c) 2010 Peter Ross <pross@xvid.org>
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  * Megalux Frame demuxer
25  */
26 
27 #include "libavcodec/raw.h"
28 #include "libavutil/imgutils.h"
29 #include "libavutil/intreadwrite.h"
30 #include "avformat.h"
31 
32 static const enum AVPixelFormat frm_pix_fmt_tags[] = {
38 };
39 
40 typedef struct {
41  int count;
42 } FrmContext;
43 
44 static int frm_read_probe(const AVProbeData *p)
45 {
46  if (p->buf_size > 8 &&
47  p->buf[0] == 'F' && p->buf[1] == 'R' && p->buf[2] == 'M' &&
48  AV_RL16(&p->buf[4]) && AV_RL16(&p->buf[6]))
49  return AVPROBE_SCORE_MAX / 4;
50  return 0;
51 }
52 
53 static int frm_read_header(AVFormatContext *avctx)
54 {
55  AVIOContext *pb = avctx->pb;
56  AVStream *st = avformat_new_stream(avctx, 0);
57  unsigned idx;
58 
59  if (!st)
60  return AVERROR(ENOMEM);
61 
64  avio_skip(pb, 3);
65 
66  idx = avio_r8(pb) - 1;
67  if (idx >= FF_ARRAY_ELEMS(frm_pix_fmt_tags))
68  return AVERROR_INVALIDDATA;
69  st->codecpar->format = frm_pix_fmt_tags[idx];
70 
71  st->codecpar->codec_tag = 0;
72  st->codecpar->width = avio_rl16(pb);
73  st->codecpar->height = avio_rl16(pb);
74  return 0;
75 }
76 
78 {
79  FrmContext *s = avctx->priv_data;
80  AVCodecParameters *par = avctx->streams[0]->codecpar;
81  int packet_size, ret;
82 
83  if (s->count)
84  return AVERROR_EOF;
85 
86  packet_size = av_image_get_buffer_size(par->format, par->width, par->height, 1);
87  if (packet_size < 0)
88  return AVERROR_INVALIDDATA;
89 
90  ret = av_get_packet(avctx->pb, pkt, packet_size);
91  if (ret < 0)
92  return ret;
93 
94  if (par->format == AV_PIX_FMT_BGRA) {
95  int i;
96  for (i = 3; i + 1 <= pkt->size; i += 4)
97  pkt->data[i] = 0xFF - pkt->data[i];
98  }
99 
100  pkt->stream_index = 0;
101  s->count++;
102 
103  return 0;
104 }
105 
107  .name = "frm",
108  .priv_data_size = sizeof(FrmContext),
109  .long_name = NULL_IF_CONFIG_SMALL("Megalux Frame"),
110  .read_probe = frm_read_probe,
111  .read_header = frm_read_header,
112  .read_packet = frm_read_packet,
113 };
Main libavformat public API header.
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:453
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
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:734
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:337
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:624
#define AV_RL16
Definition: intreadwrite.h:42
#define s(width, name)
Definition: cbs_vp9.c:257
static int frm_read_packet(AVFormatContext *avctx, AVPacket *pkt)
Definition: frmdec.c:77
static int frm_read_probe(const AVProbeData *p)
Definition: frmdec.c:44
static enum AVPixelFormat frm_pix_fmt_tags[]
Definition: frmdec.c:32
AVInputFormat ff_frm_demuxer
Definition: frmdec.c:106
static int frm_read_header(AVFormatContext *avctx)
Definition: frmdec.c:53
@ AV_CODEC_ID_RAWVIDEO
Definition: codec_id.h:62
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4509
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
#define AVERROR_EOF
End of file.
Definition: error.h:55
#define AVERROR(e)
Definition: error.h:43
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
int av_image_get_buffer_size(enum AVPixelFormat pix_fmt, int width, int height, int align)
Return the size in bytes of the amount of data required to store an image with the given parameters.
Definition: imgutils.c:466
misc image utilities
int i
Definition: input.c:407
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
@ AV_PIX_FMT_RGB24
packed RGB 8:8:8, 24bpp, RGBRGB...
Definition: pixfmt.h:68
@ AV_PIX_FMT_BGR0
packed BGR 8:8:8, 32bpp, BGRXBGRX... X=unused/undefined
Definition: pixfmt.h:240
@ AV_PIX_FMT_BGRA
packed BGRA 8:8:8:8, 32bpp, BGRABGRA...
Definition: pixfmt.h:95
@ AV_PIX_FMT_RGB0
packed RGB 8:8:8, 32bpp, RGBXRGBX... X=unused/undefined
Definition: pixfmt.h:238
#define AV_PIX_FMT_RGB555
Definition: pixfmt.h:387
Raw Video Codec.
#define FF_ARRAY_ELEMS(a)
This struct describes the properties of an encoded stream.
Definition: codec_par.h:52
int width
Video only.
Definition: codec_par.h:126
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: codec_par.h:64
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
Format I/O context.
Definition: avformat.h:1232
AVIOContext * pb
I/O context.
Definition: avformat.h:1274
void * priv_data
Format private data.
Definition: avformat.h:1260
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1300
Bytestream IO Context.
Definition: avio.h:161
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:645
This structure stores compressed data.
Definition: packet.h:346
int stream_index
Definition: packet.h:371
int size
Definition: packet.h:370
uint8_t * data
Definition: packet.h:369
This structure contains the data a format has to probe a file.
Definition: avformat.h:441
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:444
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:443
Stream structure.
Definition: avformat.h:873
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1038
int count
Definition: frmdec.c:41
AVPacket * pkt
Definition: movenc.c:59