1/*
2 * Forward Uncompressed
3 *
4 * Copyright (c) 2009 Reimar Döffinger <Reimar.Doeffinger@gmx.de>
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 "bytestream.h"
25#include "libavutil/intreadwrite.h"
26
27static av_cold int decode_init(AVCodecContext *avctx)
28{
29    if (avctx->width & 1) {
30        av_log(avctx, AV_LOG_ERROR, "FRWU needs even width\n");
31        return -1;
32    }
33    avctx->pix_fmt = PIX_FMT_UYVY422;
34
35    avctx->coded_frame = avcodec_alloc_frame();
36
37    return 0;
38}
39
40static int decode_frame(AVCodecContext *avctx, void *data, int *data_size,
41                        AVPacket *avpkt)
42{
43    int field;
44    AVFrame *pic = avctx->coded_frame;
45    const uint8_t *buf = avpkt->data;
46    const uint8_t *buf_end = buf + avpkt->size;
47
48    if (pic->data[0])
49        avctx->release_buffer(avctx, pic);
50
51    if (avpkt->size < avctx->width * 2 * avctx->height + 4 + 2*8) {
52        av_log(avctx, AV_LOG_ERROR, "Packet is too small.\n");
53        return -1;
54    }
55    if (bytestream_get_le32(&buf) != AV_RL32("FRW1")) {
56        av_log(avctx, AV_LOG_ERROR, "incorrect marker\n");
57        return -1;
58    }
59
60    pic->reference = 0;
61    if (avctx->get_buffer(avctx, pic) < 0)
62        return -1;
63
64    pic->pict_type = FF_I_TYPE;
65    pic->key_frame = 1;
66    pic->interlaced_frame = 1;
67    pic->top_field_first = 1;
68
69    for (field = 0; field < 2; field++) {
70        int i;
71        int field_h = (avctx->height + !field) >> 1;
72        int field_size, min_field_size = avctx->width * 2 * field_h;
73        uint8_t *dst = pic->data[0];
74        if (buf_end - buf < 8)
75            return -1;
76        buf += 4; // flags? 0x80 == bottom field maybe?
77        field_size = bytestream_get_le32(&buf);
78        if (field_size < min_field_size) {
79            av_log(avctx, AV_LOG_ERROR, "Field size %i is too small (required %i)\n", field_size, min_field_size);
80            return -1;
81        }
82        if (buf_end - buf < field_size) {
83            av_log(avctx, AV_LOG_ERROR, "Packet is too small, need %i, have %i\n", field_size, (int)(buf_end - buf));
84            return -1;
85        }
86        if (field)
87            dst += pic->linesize[0];
88        for (i = 0; i < field_h; i++) {
89            memcpy(dst, buf, avctx->width * 2);
90            buf += avctx->width * 2;
91            dst += pic->linesize[0] << 1;
92        }
93        buf += field_size - min_field_size;
94    }
95
96    *data_size = sizeof(AVFrame);
97    *(AVFrame*)data = *pic;
98
99    return avpkt->size;
100}
101
102static av_cold int decode_close(AVCodecContext *avctx)
103{
104    AVFrame *pic = avctx->coded_frame;
105    if (pic->data[0])
106        avctx->release_buffer(avctx, pic);
107    av_freep(&avctx->coded_frame);
108
109    return 0;
110}
111
112AVCodec frwu_decoder = {
113    "FRWU",
114    AVMEDIA_TYPE_VIDEO,
115    CODEC_ID_FRWU,
116    0,
117    decode_init,
118    NULL,
119    decode_close,
120    decode_frame,
121    CODEC_CAP_DR1,
122    .long_name = NULL_IF_CONFIG_SMALL("Forward Uncompressed"),
123};
124