1/*
2 * Forward Uncompressed
3 *
4 * Copyright (c) 2009 Reimar D��ffinger <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 "internal.h"
26#include "libavutil/opt.h"
27
28typedef struct {
29    AVClass *av_class;
30    int change_field_order;
31} FRWUContext;
32
33static av_cold int decode_init(AVCodecContext *avctx)
34{
35    if (avctx->width & 1) {
36        av_log(avctx, AV_LOG_ERROR, "frwu needs even width\n");
37        return AVERROR(EINVAL);
38    }
39    avctx->pix_fmt = AV_PIX_FMT_UYVY422;
40
41    return 0;
42}
43
44static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
45                        AVPacket *avpkt)
46{
47    FRWUContext *s = avctx->priv_data;
48    int field, ret;
49    AVFrame *pic = data;
50    const uint8_t *buf = avpkt->data;
51    const uint8_t *buf_end = buf + avpkt->size;
52
53    if (avpkt->size < avctx->width * 2 * avctx->height + 4 + 2*8) {
54        av_log(avctx, AV_LOG_ERROR, "Packet is too small.\n");
55        return AVERROR_INVALIDDATA;
56    }
57    if (bytestream_get_le32(&buf) != MKTAG('F', 'R', 'W', '1')) {
58        av_log(avctx, AV_LOG_ERROR, "incorrect marker\n");
59        return AVERROR_INVALIDDATA;
60    }
61
62    if ((ret = ff_get_buffer(avctx, pic, 0)) < 0)
63        return ret;
64
65    pic->pict_type = AV_PICTURE_TYPE_I;
66    pic->key_frame = 1;
67
68    for (field = 0; field < 2; field++) {
69        int i;
70        int field_h = (avctx->height + !field) >> 1;
71        int field_size, min_field_size = avctx->width * 2 * field_h;
72        uint8_t *dst = pic->data[0];
73        if (buf_end - buf < 8)
74            return AVERROR_INVALIDDATA;
75        buf += 4; // flags? 0x80 == bottom field maybe?
76        field_size = bytestream_get_le32(&buf);
77        if (field_size < min_field_size) {
78            av_log(avctx, AV_LOG_ERROR, "Field size %i is too small (required %i)\n", field_size, min_field_size);
79            return AVERROR_INVALIDDATA;
80        }
81        if (buf_end - buf < field_size) {
82            av_log(avctx, AV_LOG_ERROR, "Packet is too small, need %i, have %i\n", field_size, (int)(buf_end - buf));
83            return AVERROR_INVALIDDATA;
84        }
85        if (field ^ s->change_field_order) {
86            dst += pic->linesize[0];
87        } else if (s->change_field_order) {
88            dst += 2 * pic->linesize[0];
89        }
90        for (i = 0; i < field_h; i++) {
91            if (s->change_field_order && field && i == field_h - 1)
92                dst = pic->data[0];
93            memcpy(dst, buf, avctx->width * 2);
94            buf += avctx->width * 2;
95            dst += pic->linesize[0] << 1;
96        }
97        buf += field_size - min_field_size;
98    }
99
100    *got_frame = 1;
101
102    return avpkt->size;
103}
104
105static const AVOption frwu_options[] = {
106    {"change_field_order", "Change field order", offsetof(FRWUContext, change_field_order), FF_OPT_TYPE_INT,
107     {.i64 = 0}, 0, 1, AV_OPT_FLAG_DECODING_PARAM | AV_OPT_FLAG_VIDEO_PARAM},
108    {NULL}
109};
110
111static const AVClass frwu_class = {
112    .class_name = "frwu Decoder",
113    .item_name  = av_default_item_name,
114    .option     = frwu_options,
115    .version    = LIBAVUTIL_VERSION_INT,
116};
117
118AVCodec ff_frwu_decoder = {
119    .name           = "frwu",
120    .long_name      = NULL_IF_CONFIG_SMALL("Forward Uncompressed"),
121    .type           = AVMEDIA_TYPE_VIDEO,
122    .id             = AV_CODEC_ID_FRWU,
123    .priv_data_size = sizeof(FRWUContext),
124    .init           = decode_init,
125    .decode         = decode_frame,
126    .capabilities   = CODEC_CAP_DR1,
127    .priv_class     = &frwu_class,
128};
129