1 /*
2 * libquicktime yuv4 decoder
3 *
4 * Copyright (c) 2011 Carl Eugen Hoyos
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
yuv4_decode_init(AVCodecContext * avctx)26 static av_cold int yuv4_decode_init(AVCodecContext *avctx)
27 {
28 avctx->pix_fmt = AV_PIX_FMT_YUV420P;
29
30 return 0;
31 }
32
yuv4_decode_frame(AVCodecContext * avctx,void * data,int * got_frame,AVPacket * avpkt)33 static int yuv4_decode_frame(AVCodecContext *avctx, void *data,
34 int *got_frame, AVPacket *avpkt)
35 {
36 AVFrame *pic = data;
37 const uint8_t *src = avpkt->data;
38 uint8_t *y, *u, *v;
39 int i, j, ret;
40
41 if (avpkt->size < 6 * (avctx->width + 1 >> 1) * (avctx->height + 1 >> 1)) {
42 av_log(avctx, AV_LOG_ERROR, "Insufficient input data.\n");
43 return AVERROR(EINVAL);
44 }
45
46 if ((ret = ff_get_buffer(avctx, pic, 0)) < 0)
47 return ret;
48
49 pic->key_frame = 1;
50 pic->pict_type = AV_PICTURE_TYPE_I;
51
52 y = pic->data[0];
53 u = pic->data[1];
54 v = pic->data[2];
55
56 for (i = 0; i < (avctx->height + 1) >> 1; i++) {
57 for (j = 0; j < (avctx->width + 1) >> 1; j++) {
58 u[j] = *src++ ^ 0x80;
59 v[j] = *src++ ^ 0x80;
60 y[ 2 * j ] = *src++;
61 y[ 2 * j + 1] = *src++;
62 y[pic->linesize[0] + 2 * j ] = *src++;
63 y[pic->linesize[0] + 2 * j + 1] = *src++;
64 }
65
66 y += 2 * pic->linesize[0];
67 u += pic->linesize[1];
68 v += pic->linesize[2];
69 }
70
71 *got_frame = 1;
72
73 return avpkt->size;
74 }
75
76 AVCodec ff_yuv4_decoder = {
77 .name = "yuv4",
78 .long_name = NULL_IF_CONFIG_SMALL("Uncompressed packed 4:2:0"),
79 .type = AVMEDIA_TYPE_VIDEO,
80 .id = AV_CODEC_ID_YUV4,
81 .init = yuv4_decode_init,
82 .decode = yuv4_decode_frame,
83 .capabilities = AV_CODEC_CAP_DR1,
84 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
85 };
86