FFmpeg  2.1.1
avrndec.c
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1 /*
2  * AVRn decoder
3  * Copyright (c) 2012 Michael Niedermayer
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 "avcodec.h"
23 #include "internal.h"
24 #include "mjpeg.h"
25 #include "mjpegdec.h"
26 #include "libavutil/imgutils.h"
27 
28 typedef struct {
30  int is_mjpeg;
31  int interlace; //FIXME use frame.interlaced_frame
32  int tff;
33 } AVRnContext;
34 
35 static av_cold int init(AVCodecContext *avctx)
36 {
37  AVRnContext *a = avctx->priv_data;
38  int ret;
39 
40  // Support "Resolution 1:1" for Avid AVI Codec
41  a->is_mjpeg = avctx->extradata_size < 31 || memcmp(&avctx->extradata[28], "1:1", 3);
42 
43  if(!a->is_mjpeg && avctx->lowres) {
44  av_log(avctx, AV_LOG_ERROR, "lowres is not possible with rawvideo\n");
45  return AVERROR(EINVAL);
46  }
47 
48  if(a->is_mjpeg)
49  return ff_mjpeg_decode_init(avctx);
50 
51  if ((ret = av_image_check_size(avctx->width, avctx->height, 0, avctx)) < 0)
52  return ret;
53 
54  avctx->pix_fmt = AV_PIX_FMT_UYVY422;
55 
56  if(avctx->extradata_size >= 9 && avctx->extradata[4]+28 < avctx->extradata_size) {
57  int ndx = avctx->extradata[4] + 4;
58  a->interlace = !memcmp(avctx->extradata + ndx, "1:1(", 4);
59  if(a->interlace) {
60  a->tff = avctx->extradata[ndx + 24] == 1;
61  }
62  }
63 
64  return 0;
65 }
66 
67 static av_cold int end(AVCodecContext *avctx)
68 {
69  AVRnContext *a = avctx->priv_data;
70 
71  if(a->is_mjpeg)
72  ff_mjpeg_decode_end(avctx);
73 
74  return 0;
75 }
76 
77 static int decode_frame(AVCodecContext *avctx, void *data,
78  int *got_frame, AVPacket *avpkt)
79 {
80  AVRnContext *a = avctx->priv_data;
81  AVFrame *p = data;
82  const uint8_t *buf = avpkt->data;
83  int buf_size = avpkt->size;
84  int y, ret, true_height;
85 
86  if(a->is_mjpeg)
87  return ff_mjpeg_decode_frame(avctx, data, got_frame, avpkt);
88 
89  true_height = buf_size / (2*avctx->width);
90 
91  if(buf_size < 2*avctx->width * avctx->height) {
92  av_log(avctx, AV_LOG_ERROR, "packet too small\n");
93  return AVERROR_INVALIDDATA;
94  }
95 
96  if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
97  return ret;
99  p->key_frame= 1;
100 
101  if(a->interlace) {
102  buf += (true_height - avctx->height)*avctx->width;
103  for(y = 0; y < avctx->height-1; y+=2) {
104  memcpy(p->data[0] + (y+ a->tff)*p->linesize[0], buf , 2*avctx->width);
105  memcpy(p->data[0] + (y+!a->tff)*p->linesize[0], buf + avctx->width*true_height+4, 2*avctx->width);
106  buf += 2*avctx->width;
107  }
108  } else {
109  buf += (true_height - avctx->height)*avctx->width*2;
110  for(y = 0; y < avctx->height; y++) {
111  memcpy(p->data[0] + y*p->linesize[0], buf, 2*avctx->width);
112  buf += 2*avctx->width;
113  }
114  }
115 
116  *got_frame = 1;
117  return buf_size;
118 }
119 
121  .name = "avrn",
122  .long_name = NULL_IF_CONFIG_SMALL("Avid AVI Codec"),
123  .type = AVMEDIA_TYPE_VIDEO,
124  .id = AV_CODEC_ID_AVRN,
125  .priv_data_size = sizeof(AVRnContext),
126  .init = init,
127  .close = end,
128  .decode = decode_frame,
129  .capabilities = CODEC_CAP_DR1,
130  .max_lowres = 3,
131 };
AVCodec ff_avrn_decoder
Definition: avrndec.c:120
This structure describes decoded (raw) audio or video data.
Definition: frame.h:96
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: avrndec.c:77
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
int size
Definition: avcodec.h:1064
void av_log(void *avcl, int level, const char *fmt,...) av_printf_format(3
Send the specified message to the log if the level is less than or equal to the current av_log_level...
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1342
AVCodec.
Definition: avcodec.h:2922
#define av_cold
Definition: avcodec.h:653
MJPEG encoder and decoder.
int is_mjpeg
Definition: avrndec.c:30
MJpegDecodeContext mjpeg_ctx
Definition: avrndec.c:29
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1254
uint8_t
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:67
const char * name
Name of the codec implementation.
Definition: avcodec.h:2929
#define CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:742
const char data[16]
Definition: mxf.c:68
int lowres
low resolution decoding, 1-&gt; 1/2 size, 2-&gt;1/4 size
Definition: avcodec.h:2580
int ff_mjpeg_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: mjpegdec.c:1776
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: avcodec.h:4147
av_cold int ff_mjpeg_decode_end(AVCodecContext *avctx)
Definition: mjpegdec.c:2029
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:151
int interlace
Definition: avrndec.c:31
Libavcodec external API header.
int av_image_check_size(unsigned int w, unsigned int h, int log_offset, void *log_ctx)
Check if the given dimension of an image is valid, meaning that all bytes of the image can be address...
Definition: imgutils.c:231
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:167
float y
ret
Definition: avfilter.c:961
int width
picture width / height.
Definition: avcodec.h:1314
static int width
Definition: utils.c:158
main external API structure.
Definition: avcodec.h:1146
static void close(AVCodecParserContext *s)
Definition: h264_parser.c:538
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: utils.c:941
void * buf
Definition: avisynth_c.h:594
int extradata_size
Definition: avcodec.h:1255
BYTE int const BYTE int int int height
Definition: avisynth_c.h:713
uint8_t * data
Definition: avcodec.h:1063
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:124
void * priv_data
Definition: avcodec.h:1182
av_cold int ff_mjpeg_decode_init(AVCodecContext *avctx)
Definition: mjpegdec.c:86
common internal api header.
packed YUV 4:2:2, 16bpp, Cb Y0 Cr Y1
Definition: avcodec.h:4551
#define AVERROR_INVALIDDATA
int key_frame
1 -&gt; keyframe, 0-&gt; not
Definition: frame.h:162
#define AVERROR(e)
static int decode(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: crystalhd.c:868
int tff
Definition: avrndec.c:32
MJPEG decoder.
This structure stores compressed data.
Definition: avcodec.h:1040
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:107