1/*
2 * ATI VCR1 codec
3 * Copyright (c) 2003 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/**
23 * @file
24 * ATI VCR1 codec
25 */
26
27#include "avcodec.h"
28#include "internal.h"
29#include "libavutil/avassert.h"
30#include "libavutil/internal.h"
31
32typedef struct VCR1Context {
33    int delta[16];
34    int offset[4];
35} VCR1Context;
36
37static av_cold int vcr1_decode_init(AVCodecContext *avctx)
38{
39    avctx->pix_fmt = AV_PIX_FMT_YUV410P;
40
41    if (avctx->width % 8 || avctx->height%4) {
42        avpriv_request_sample(avctx, "odd dimensions (%d x %d) support", avctx->width, avctx->height);
43        return AVERROR_INVALIDDATA;
44    }
45
46    return 0;
47}
48
49static int vcr1_decode_frame(AVCodecContext *avctx, void *data,
50                             int *got_frame, AVPacket *avpkt)
51{
52    VCR1Context *const a      = avctx->priv_data;
53    AVFrame *const p          = data;
54    const uint8_t *bytestream = avpkt->data;
55    const uint8_t *bytestream_end = bytestream + avpkt->size;
56    int i, x, y, ret;
57
58    if(avpkt->size < 32 + avctx->height + avctx->width*avctx->height*5/8){
59        av_log(avctx, AV_LOG_ERROR, "Insufficient input data. %d < %d\n", avpkt->size ,  32 + avctx->height + avctx->width*avctx->height*5/8);
60        return AVERROR(EINVAL);
61    }
62
63    if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
64        return ret;
65    p->pict_type = AV_PICTURE_TYPE_I;
66    p->key_frame = 1;
67
68    for (i = 0; i < 16; i++) {
69        a->delta[i] = *bytestream++;
70        bytestream++;
71    }
72
73    for (y = 0; y < avctx->height; y++) {
74        int offset;
75        uint8_t *luma = &p->data[0][y * p->linesize[0]];
76
77        if ((y & 3) == 0) {
78            uint8_t *cb = &p->data[1][(y >> 2) * p->linesize[1]];
79            uint8_t *cr = &p->data[2][(y >> 2) * p->linesize[2]];
80
81            av_assert0 (bytestream_end - bytestream >= 4 + avctx->width);
82
83            for (i = 0; i < 4; i++)
84                a->offset[i] = *bytestream++;
85
86            offset = a->offset[0] - a->delta[bytestream[2] & 0xF];
87            for (x = 0; x < avctx->width; x += 4) {
88                luma[0]     = offset += a->delta[bytestream[2] & 0xF];
89                luma[1]     = offset += a->delta[bytestream[2] >>  4];
90                luma[2]     = offset += a->delta[bytestream[0] & 0xF];
91                luma[3]     = offset += a->delta[bytestream[0] >>  4];
92                luma       += 4;
93
94                *cb++       = bytestream[3];
95                *cr++       = bytestream[1];
96
97                bytestream += 4;
98            }
99        } else {
100            av_assert0 (bytestream_end - bytestream >= avctx->width / 2);
101
102            offset = a->offset[y & 3] - a->delta[bytestream[2] & 0xF];
103
104            for (x = 0; x < avctx->width; x += 8) {
105                luma[0]     = offset += a->delta[bytestream[2] & 0xF];
106                luma[1]     = offset += a->delta[bytestream[2] >>  4];
107                luma[2]     = offset += a->delta[bytestream[3] & 0xF];
108                luma[3]     = offset += a->delta[bytestream[3] >>  4];
109                luma[4]     = offset += a->delta[bytestream[0] & 0xF];
110                luma[5]     = offset += a->delta[bytestream[0] >>  4];
111                luma[6]     = offset += a->delta[bytestream[1] & 0xF];
112                luma[7]     = offset += a->delta[bytestream[1] >>  4];
113                luma       += 8;
114                bytestream += 4;
115            }
116        }
117    }
118
119    *got_frame = 1;
120
121    return bytestream - avpkt->data;
122}
123
124AVCodec ff_vcr1_decoder = {
125    .name           = "vcr1",
126    .long_name      = NULL_IF_CONFIG_SMALL("ATI VCR1"),
127    .type           = AVMEDIA_TYPE_VIDEO,
128    .id             = AV_CODEC_ID_VCR1,
129    .priv_data_size = sizeof(VCR1Context),
130    .init           = vcr1_decode_init,
131    .decode         = vcr1_decode_frame,
132    .capabilities   = CODEC_CAP_DR1,
133};
134