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 "mjpeg.h"
25 #include "mjpegdec.h"
26 #include "libavutil/imgutils.h"
27 
28 typedef struct {
29     AVCodecContext *mjpeg_avctx;
30     int is_mjpeg;
31     int interlace;
32     int tff;
33 } AVRnContext;
34 
init(AVCodecContext * avctx)35 static av_cold int init(AVCodecContext *avctx)
36 {
37     AVRnContext *a = avctx->priv_data;
38     int ret;
39 
40     // Support "Resolution 1:1" for Avid AVI Codec
41     a->is_mjpeg = avctx->extradata_size < 31 || memcmp(&avctx->extradata[28], "1:1", 3);
42 
43     if(!a->is_mjpeg && avctx->lowres) {
44         av_log(avctx, AV_LOG_ERROR, "lowres is not possible with rawvideo\n");
45         return AVERROR(EINVAL);
46     }
47 
48     if(a->is_mjpeg) {
49         AVCodec *codec = avcodec_find_decoder(AV_CODEC_ID_MJPEG);
50         AVDictionary *thread_opt = NULL;
51         if (!codec) {
52             av_log(avctx, AV_LOG_ERROR, "MJPEG codec not found\n");
53             return AVERROR_DECODER_NOT_FOUND;
54         }
55 
56         a->mjpeg_avctx = avcodec_alloc_context3(codec);
57 
58         av_dict_set(&thread_opt, "threads", "1", 0); // Is this needed ?
59         a->mjpeg_avctx->refcounted_frames = 1;
60         a->mjpeg_avctx->flags = avctx->flags;
61         a->mjpeg_avctx->idct_algo = avctx->idct_algo;
62         a->mjpeg_avctx->lowres = avctx->lowres;
63         a->mjpeg_avctx->width = avctx->width;
64         a->mjpeg_avctx->height = avctx->height;
65 
66         if ((ret = ff_codec_open2_recursive(a->mjpeg_avctx, codec, &thread_opt)) < 0) {
67             av_log(avctx, AV_LOG_ERROR, "MJPEG codec failed to open\n");
68         }
69         av_dict_free(&thread_opt);
70 
71         return ret;
72     }
73 
74     if ((ret = av_image_check_size(avctx->width, avctx->height, 0, avctx)) < 0)
75         return ret;
76 
77     avctx->pix_fmt = AV_PIX_FMT_UYVY422;
78 
79     if(avctx->extradata_size >= 9 && avctx->extradata[4]+28 < avctx->extradata_size) {
80         int ndx = avctx->extradata[4] + 4;
81         a->interlace = !memcmp(avctx->extradata + ndx, "1:1(", 4);
82         if(a->interlace) {
83             a->tff = avctx->extradata[ndx + 24] == 1;
84         }
85     }
86 
87     return 0;
88 }
89 
end(AVCodecContext * avctx)90 static av_cold int end(AVCodecContext *avctx)
91 {
92     AVRnContext *a = avctx->priv_data;
93 
94     avcodec_close(a->mjpeg_avctx);
95     av_freep(&a->mjpeg_avctx);
96 
97     return 0;
98 }
99 
decode_frame(AVCodecContext * avctx,void * data,int * got_frame,AVPacket * avpkt)100 static int decode_frame(AVCodecContext *avctx, void *data,
101                         int *got_frame, AVPacket *avpkt)
102 {
103     AVRnContext *a = avctx->priv_data;
104     AVFrame *p = data;
105     const uint8_t *buf = avpkt->data;
106     int buf_size       = avpkt->size;
107     int y, ret, true_height;
108 
109     if(a->is_mjpeg) {
110         ret = avcodec_decode_video2(a->mjpeg_avctx, data, got_frame, avpkt);
111 
112         if (ret >= 0 && *got_frame && avctx->width <= p->width && avctx->height <= p->height) {
113             int shift = p->height - avctx->height;
114             int subsample_h, subsample_v;
115 
116             av_pix_fmt_get_chroma_sub_sample(p->format, &subsample_h, &subsample_v);
117 
118             p->data[0] += p->linesize[0] * shift;
119             if (p->data[2]) {
120                 p->data[1] += p->linesize[1] * (shift>>subsample_v);
121                 p->data[2] += p->linesize[2] * (shift>>subsample_v);
122             }
123 
124             p->width  = avctx->width;
125             p->height = avctx->height;
126         }
127         avctx->pix_fmt = a->mjpeg_avctx->pix_fmt;
128         return ret;
129     }
130 
131     true_height    = buf_size / (2*avctx->width);
132 
133     if(buf_size < 2*avctx->width * avctx->height) {
134         av_log(avctx, AV_LOG_ERROR, "packet too small\n");
135         return AVERROR_INVALIDDATA;
136     }
137 
138     if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
139         return ret;
140     p->pict_type= AV_PICTURE_TYPE_I;
141     p->key_frame= 1;
142 
143     if(a->interlace) {
144         buf += (true_height - avctx->height)*avctx->width;
145         for(y = 0; y < avctx->height-1; y+=2) {
146             memcpy(p->data[0] + (y+ a->tff)*p->linesize[0], buf                             , 2*avctx->width);
147             memcpy(p->data[0] + (y+!a->tff)*p->linesize[0], buf + avctx->width*true_height+4, 2*avctx->width);
148             buf += 2*avctx->width;
149         }
150     } else {
151         buf += (true_height - avctx->height)*avctx->width*2;
152         for(y = 0; y < avctx->height; y++) {
153             memcpy(p->data[0] + y*p->linesize[0], buf, 2*avctx->width);
154             buf += 2*avctx->width;
155         }
156     }
157 
158     *got_frame      = 1;
159     return buf_size;
160 }
161 
162 AVCodec ff_avrn_decoder = {
163     .name           = "avrn",
164     .long_name      = NULL_IF_CONFIG_SMALL("Avid AVI Codec"),
165     .type           = AVMEDIA_TYPE_VIDEO,
166     .id             = AV_CODEC_ID_AVRN,
167     .priv_data_size = sizeof(AVRnContext),
168     .init           = init,
169     .close          = end,
170     .decode         = decode_frame,
171     .max_lowres     = 3,
172     .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
173 };
174