xref: /third_party/ffmpeg/libavcodec/bitpacked.c (revision cabdff1a) 
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
34struct BitpackedContext {
35    int (*decode)(AVCodecContext *avctx, AVFrame *frame,
36                  const AVPacket *pkt);
37};
38
39/* For this format, it's a simple passthrough */
40static 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
58static 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
97static 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
120static 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
140AVCodec 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