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y41pdec.c
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1 /*
2  * y41p decoder
3  *
4  * Copyright (c) 2012 Paul B Mahol
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #include "avcodec.h"
24 #include "internal.h"
25 
27 {
28  avctx->pix_fmt = AV_PIX_FMT_YUV411P;
29  avctx->bits_per_raw_sample = 12;
30 
31  if (avctx->width & 7) {
32  av_log(avctx, AV_LOG_WARNING, "y41p requires width to be divisible by 8.\n");
33  }
34 
35  return 0;
36 }
37 
38 static int y41p_decode_frame(AVCodecContext *avctx, void *data,
39  int *got_frame, AVPacket *avpkt)
40 {
41  AVFrame *pic = data;
42  uint8_t *src = avpkt->data;
43  uint8_t *y, *u, *v;
44  int i, j, ret;
45 
46  if (avpkt->size < 1.5 * avctx->height * avctx->width) {
47  av_log(avctx, AV_LOG_ERROR, "Insufficient input data.\n");
48  return AVERROR(EINVAL);
49  }
50 
51  if ((ret = ff_get_buffer(avctx, pic, 0)) < 0)
52  return ret;
53 
54  pic->key_frame = 1;
56 
57  for (i = avctx->height - 1; i >= 0 ; i--) {
58  y = &pic->data[0][i * pic->linesize[0]];
59  u = &pic->data[1][i * pic->linesize[1]];
60  v = &pic->data[2][i * pic->linesize[2]];
61  for (j = 0; j < avctx->width; j += 8) {
62  *(u++) = *src++;
63  *(y++) = *src++;
64  *(v++) = *src++;
65  *(y++) = *src++;
66 
67  *(u++) = *src++;
68  *(y++) = *src++;
69  *(v++) = *src++;
70  *(y++) = *src++;
71 
72  *(y++) = *src++;
73  *(y++) = *src++;
74  *(y++) = *src++;
75  *(y++) = *src++;
76  }
77  }
78 
79  *got_frame = 1;
80 
81  return avpkt->size;
82 }
83 
85  .name = "y41p",
86  .type = AVMEDIA_TYPE_VIDEO,
87  .id = AV_CODEC_ID_Y41P,
88  .init = y41p_decode_init,
89  .decode = y41p_decode_frame,
90  .capabilities = CODEC_CAP_DR1,
91  .long_name = NULL_IF_CONFIG_SMALL("Uncompressed YUV 4:1:1 12-bit"),
92 };