1 /*
2 * AVRn decoder
3 * Copyright (c) 2012 Michael Niedermayer
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 #include "avcodec.h"
23 #include "internal.h"
24 #include "libavutil/imgutils.h"
25
26 typedef struct {
27 int interlace;
28 int tff;
29 } AVRnContext;
30
init(AVCodecContext * avctx)31 static av_cold int init(AVCodecContext *avctx)
32 {
33 AVRnContext *a = avctx->priv_data;
34 int ret;
35
36 if ((ret = av_image_check_size(avctx->width, avctx->height, 0, avctx)) < 0)
37 return ret;
38
39 avctx->pix_fmt = AV_PIX_FMT_UYVY422;
40
41 if(avctx->extradata_size >= 9 && avctx->extradata[4]+28 < avctx->extradata_size) {
42 int ndx = avctx->extradata[4] + 4;
43 a->interlace = !memcmp(avctx->extradata + ndx, "1:1(", 4);
44 if(a->interlace) {
45 a->tff = avctx->extradata[ndx + 24] == 1;
46 }
47 }
48
49 return 0;
50 }
51
decode_frame(AVCodecContext * avctx,void * data,int * got_frame,AVPacket * avpkt)52 static int decode_frame(AVCodecContext *avctx, void *data,
53 int *got_frame, AVPacket *avpkt)
54 {
55 AVRnContext *a = avctx->priv_data;
56 AVFrame *p = data;
57 const uint8_t *buf = avpkt->data;
58 int buf_size = avpkt->size;
59 int y, ret, true_height;
60
61 true_height = buf_size / (2*avctx->width);
62
63 if(buf_size < 2*avctx->width * avctx->height) {
64 av_log(avctx, AV_LOG_ERROR, "packet too small\n");
65 return AVERROR_INVALIDDATA;
66 }
67
68 if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
69 return ret;
70 p->pict_type= AV_PICTURE_TYPE_I;
71 p->key_frame= 1;
72
73 if(a->interlace) {
74 buf += (true_height - avctx->height)*avctx->width;
75 for(y = 0; y < avctx->height-1; y+=2) {
76 memcpy(p->data[0] + (y+ a->tff)*p->linesize[0], buf , 2*avctx->width);
77 memcpy(p->data[0] + (y+!a->tff)*p->linesize[0], buf + avctx->width*true_height+4, 2*avctx->width);
78 buf += 2*avctx->width;
79 }
80 } else {
81 buf += (true_height - avctx->height)*avctx->width*2;
82 for(y = 0; y < avctx->height; y++) {
83 memcpy(p->data[0] + y*p->linesize[0], buf, 2*avctx->width);
84 buf += 2*avctx->width;
85 }
86 }
87
88 *got_frame = 1;
89 return buf_size;
90 }
91
92 AVCodec ff_avrn_decoder = {
93 .name = "avrn",
94 .long_name = NULL_IF_CONFIG_SMALL("Avid AVI Codec"),
95 .type = AVMEDIA_TYPE_VIDEO,
96 .id = AV_CODEC_ID_AVRN,
97 .priv_data_size = sizeof(AVRnContext),
98 .init = init,
99 .decode = decode_frame,
100 .capabilities = AV_CODEC_CAP_DR1,
101 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP,
102 };
103