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
26static av_cold int yuv4_decode_init(AVCodecContext *avctx)
27{
28    avctx->pix_fmt = AV_PIX_FMT_YUV420P;
29
30    return 0;
31}
32
33static 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
76AVCodec 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 = CODEC_CAP_DR1,
84};
85