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 "internal.h"
26 #include "libavutil/opt.h"
27
28 typedef struct {
29 AVClass *av_class;
30 int change_field_order;
31 } FRWUContext;
32
decode_init(AVCodecContext * avctx)33 static 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
decode_frame(AVCodecContext * avctx,void * data,int * got_frame,AVPacket * avpkt)44 static 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
105 static const AVOption frwu_options[] = {
106 {"change_field_order", "Change field order", offsetof(FRWUContext, change_field_order), AV_OPT_TYPE_BOOL,
107 {.i64 = 0}, 0, 1, AV_OPT_FLAG_DECODING_PARAM | AV_OPT_FLAG_VIDEO_PARAM},
108 {NULL}
109 };
110
111 static 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
118 AVCodec 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 = AV_CODEC_CAP_DR1,
127 .priv_class = &frwu_class,
128 };
129