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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 {
31  int is_mjpeg;
32  int interlace; //FIXME use frame.interlaced_frame
33  int tff;
34 } AVRnContext;
35 
36 static av_cold int init(AVCodecContext *avctx)
37 {
38  AVRnContext *a = avctx->priv_data;
39  int ret;
40 
41  // Support "Resolution 1:1" for Avid AVI Codec
42  a->is_mjpeg = avctx->extradata_size < 31 || memcmp(&avctx->extradata[28], "1:1", 3);
43 
44  if(!a->is_mjpeg && avctx->lowres) {
45  av_log(avctx, AV_LOG_ERROR, "lowres is not possible with rawvideo\n");
46  return AVERROR(EINVAL);
47  }
48 
49  if(a->is_mjpeg)
50  return ff_mjpeg_decode_init(avctx);
51 
52  if ((ret = av_image_check_size(avctx->width, avctx->height, 0, avctx)) < 0)
53  return ret;
54 
56  avctx->pix_fmt = AV_PIX_FMT_UYVY422;
57 
58  if(avctx->extradata_size >= 9 && avctx->extradata[4]+28 < avctx->extradata_size) {
59  int ndx = avctx->extradata[4] + 4;
60  a->interlace = !memcmp(avctx->extradata + ndx, "1:1(", 4);
61  if(a->interlace) {
62  a->tff = avctx->extradata[ndx + 24] == 1;
63  }
64  }
65 
66  return 0;
67 }
68 
69 static av_cold int end(AVCodecContext *avctx)
70 {
71  AVRnContext *a = avctx->priv_data;
72  AVFrame *p = &a->frame;
73 
74  if(p->data[0])
75  avctx->release_buffer(avctx, p);
76 
77  if(a->is_mjpeg)
78  ff_mjpeg_decode_end(avctx);
79 
80  return 0;
81 }
82 
83 static int decode_frame(AVCodecContext *avctx, void *data,
84  int *got_frame, AVPacket *avpkt)
85 {
86  AVRnContext *a = avctx->priv_data;
87  AVFrame *p = &a->frame;
88  const uint8_t *buf = avpkt->data;
89  int buf_size = avpkt->size;
90  int y, ret, true_height;
91 
92  if(a->is_mjpeg)
93  return ff_mjpeg_decode_frame(avctx, data, got_frame, avpkt);
94 
95  true_height = buf_size / (2*avctx->width);
96  if(p->data[0])
97  avctx->release_buffer(avctx, p);
98 
99  if(buf_size < 2*avctx->width * avctx->height) {
100  av_log(avctx, AV_LOG_ERROR, "packet too small\n");
101  return AVERROR_INVALIDDATA;
102  }
103 
104  if((ret = ff_get_buffer(avctx, p)) < 0){
105  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
106  return ret;
107  }
109  p->key_frame= 1;
110 
111  if(a->interlace) {
112  buf += (true_height - avctx->height)*avctx->width;
113  for(y = 0; y < avctx->height-1; y+=2) {
114  memcpy(p->data[0] + (y+ a->tff)*p->linesize[0], buf , 2*avctx->width);
115  memcpy(p->data[0] + (y+!a->tff)*p->linesize[0], buf + avctx->width*true_height+4, 2*avctx->width);
116  buf += 2*avctx->width;
117  }
118  } else {
119  buf += (true_height - avctx->height)*avctx->width*2;
120  for(y = 0; y < avctx->height; y++) {
121  memcpy(p->data[0] + y*p->linesize[0], buf, 2*avctx->width);
122  buf += 2*avctx->width;
123  }
124  }
125 
126  *(AVFrame*)data = a->frame;
127  *got_frame = 1;
128  return buf_size;
129 }
130 
132  .name = "avrn",
133  .type = AVMEDIA_TYPE_VIDEO,
134  .id = AV_CODEC_ID_AVRN,
135  .priv_data_size = sizeof(AVRnContext),
136  .init = init,
137  .close = end,
138  .decode = decode_frame,
139  .long_name = NULL_IF_CONFIG_SMALL("Avid AVI Codec"),
140  .capabilities = CODEC_CAP_DR1,
141  .max_lowres = 3,
142 };
143