1 /*
2  * Unpack bit-packed streams to formats supported by FFmpeg
3  * Copyright (c) 2017 Savoir-faire Linux, Inc
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 /* Development sponsored by CBC/Radio-Canada */
23 
24 /**
25  * @file
26  * Bitpacked
27  */
28 
29 #include "avcodec.h"
30 #include "internal.h"
31 #include "get_bits.h"
32 #include "libavutil/imgutils.h"
33 
34 struct BitpackedContext {
35     int (*decode)(AVCodecContext *avctx, AVFrame *frame,
36                   const AVPacket *pkt);
37 };
38 
39 /* For this format, it's a simple passthrough */
bitpacked_decode_uyvy422(AVCodecContext * avctx,AVFrame * frame,const AVPacket * avpkt)40 static int bitpacked_decode_uyvy422(AVCodecContext *avctx, AVFrame *frame,
41                                     const AVPacket *avpkt)
42 {
43     int ret;
44 
45     /* there is no need to copy as the data already match
46      * a known pixel format */
47     frame->buf[0] = av_buffer_ref(avpkt->buf);
48     ret = av_image_fill_arrays(frame->data, frame->linesize, avpkt->data,
49                                avctx->pix_fmt, avctx->width, avctx->height, 1);
50     if (ret < 0) {
51         av_buffer_unref(&frame->buf[0]);
52         return ret;
53     }
54 
55     return 0;
56 }
57 
bitpacked_decode_yuv422p10(AVCodecContext * avctx,AVFrame * frame,const AVPacket * avpkt)58 static int bitpacked_decode_yuv422p10(AVCodecContext *avctx, AVFrame *frame,
59                                       const AVPacket *avpkt)
60 {
61     uint64_t frame_size = (uint64_t)avctx->width * (uint64_t)avctx->height * 20;
62     uint64_t packet_size = (uint64_t)avpkt->size * 8;
63     GetBitContext bc;
64     uint16_t *y, *u, *v;
65     int ret, i, j;
66 
67     ret = ff_get_buffer(avctx, frame, 0);
68     if (ret < 0)
69         return ret;
70 
71     if (frame_size > packet_size)
72         return AVERROR_INVALIDDATA;
73 
74     if (avctx->width % 2)
75         return AVERROR_PATCHWELCOME;
76 
77     ret = init_get_bits(&bc, avpkt->data, avctx->width * avctx->height * 20);
78     if (ret)
79         return ret;
80 
81     for (i = 0; i < avctx->height; i++) {
82         y = (uint16_t*)(frame->data[0] + i * frame->linesize[0]);
83         u = (uint16_t*)(frame->data[1] + i * frame->linesize[1]);
84         v = (uint16_t*)(frame->data[2] + i * frame->linesize[2]);
85 
86         for (j = 0; j < avctx->width; j += 2) {
87             *u++ = get_bits(&bc, 10);
88             *y++ = get_bits(&bc, 10);
89             *v++ = get_bits(&bc, 10);
90             *y++ = get_bits(&bc, 10);
91         }
92     }
93 
94     return 0;
95 }
96 
bitpacked_init_decoder(AVCodecContext * avctx)97 static av_cold int bitpacked_init_decoder(AVCodecContext *avctx)
98 {
99     struct BitpackedContext *bc = avctx->priv_data;
100 
101     if (!avctx->codec_tag || !avctx->width || !avctx->height)
102         return AVERROR_INVALIDDATA;
103 
104     if (avctx->codec_tag == MKTAG('U', 'Y', 'V', 'Y')) {
105         if (avctx->bits_per_coded_sample == 16 &&
106             avctx->pix_fmt == AV_PIX_FMT_UYVY422)
107             bc->decode = bitpacked_decode_uyvy422;
108         else if (avctx->bits_per_coded_sample == 20 &&
109                  avctx->pix_fmt == AV_PIX_FMT_YUV422P10)
110             bc->decode = bitpacked_decode_yuv422p10;
111         else
112             return AVERROR_INVALIDDATA;
113     } else {
114         return AVERROR_INVALIDDATA;
115     }
116 
117     return 0;
118 }
119 
bitpacked_decode(AVCodecContext * avctx,void * data,int * got_frame,AVPacket * avpkt)120 static int bitpacked_decode(AVCodecContext *avctx, void *data, int *got_frame,
121                             AVPacket *avpkt)
122 {
123     struct BitpackedContext *bc = avctx->priv_data;
124     int buf_size = avpkt->size;
125     AVFrame *frame = data;
126     int res;
127 
128     frame->pict_type = AV_PICTURE_TYPE_I;
129     frame->key_frame = 1;
130 
131     res = bc->decode(avctx, frame, avpkt);
132     if (res)
133         return res;
134 
135     *got_frame = 1;
136     return buf_size;
137 
138 }
139 
140 AVCodec ff_bitpacked_decoder = {
141     .name   = "bitpacked",
142     .long_name = NULL_IF_CONFIG_SMALL("Bitpacked"),
143     .type = AVMEDIA_TYPE_VIDEO,
144     .id = AV_CODEC_ID_BITPACKED,
145     .priv_data_size        = sizeof(struct BitpackedContext),
146     .init = bitpacked_init_decoder,
147     .decode = bitpacked_decode,
148     .capabilities = AV_CODEC_CAP_EXPERIMENTAL,
149     .codec_tags     = (const uint32_t []){
150         MKTAG('U', 'Y', 'V', 'Y'),
151         FF_CODEC_TAGS_END,
152     },
153 };
154