3 * Copyright (c) 2003 Michael Niedermayer
5 * This file is part of Libav.
7 * Libav 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.
12 * Libav 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.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with Libav; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
29 #include "libavutil/internal.h"
31 typedef struct VCR1Context {
36 static av_cold int vcr1_decode_init(AVCodecContext *avctx)
38 avctx->pix_fmt = AV_PIX_FMT_YUV410P;
40 if (avctx->width & 7) {
41 av_log(avctx, AV_LOG_ERROR, "Width %d is not divisble by 8.\n", avctx->width);
42 return AVERROR_INVALIDDATA;
48 static int vcr1_decode_frame(AVCodecContext *avctx, void *data,
49 int *got_frame, AVPacket *avpkt)
51 const uint8_t *buf = avpkt->data;
52 int buf_size = avpkt->size;
53 VCR1Context *const a = avctx->priv_data;
54 AVFrame *const p = data;
55 const uint8_t *bytestream = buf;
58 if ((ret = ff_get_buffer(avctx, p, 0)) < 0) {
59 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
62 p->pict_type = AV_PICTURE_TYPE_I;
68 for (i = 0; i < 16; i++) {
69 a->delta[i] = *bytestream++;
74 for (y = 0; y < avctx->height; y++) {
76 uint8_t *luma = &p->data[0][y * p->linesize[0]];
79 uint8_t *cb = &p->data[1][(y >> 2) * p->linesize[1]];
80 uint8_t *cr = &p->data[2][(y >> 2) * p->linesize[2]];
82 if (buf_size < 4 + avctx->width)
85 for (i = 0; i < 4; i++)
86 a->offset[i] = *bytestream++;
89 offset = a->offset[0] - a->delta[bytestream[2] & 0xF];
90 for (x = 0; x < avctx->width; x += 4) {
91 luma[0] = offset += a->delta[bytestream[2] & 0xF];
92 luma[1] = offset += a->delta[bytestream[2] >> 4];
93 luma[2] = offset += a->delta[bytestream[0] & 0xF];
94 luma[3] = offset += a->delta[bytestream[0] >> 4];
97 *cb++ = bytestream[3];
98 *cr++ = bytestream[1];
104 if (buf_size < avctx->width / 2)
107 offset = a->offset[y & 3] - a->delta[bytestream[2] & 0xF];
109 for (x = 0; x < avctx->width; x += 8) {
110 luma[0] = offset += a->delta[bytestream[2] & 0xF];
111 luma[1] = offset += a->delta[bytestream[2] >> 4];
112 luma[2] = offset += a->delta[bytestream[3] & 0xF];
113 luma[3] = offset += a->delta[bytestream[3] >> 4];
114 luma[4] = offset += a->delta[bytestream[0] & 0xF];
115 luma[5] = offset += a->delta[bytestream[0] >> 4];
116 luma[6] = offset += a->delta[bytestream[1] & 0xF];
117 luma[7] = offset += a->delta[bytestream[1] >> 4];
129 av_log(avctx, AV_LOG_ERROR, "Input packet too small.\n");
130 return AVERROR_INVALIDDATA;
133 AVCodec ff_vcr1_decoder = {
135 .long_name = NULL_IF_CONFIG_SMALL("ATI VCR1"),
136 .type = AVMEDIA_TYPE_VIDEO,
137 .id = AV_CODEC_ID_VCR1,
138 .priv_data_size = sizeof(VCR1Context),
139 .init = vcr1_decode_init,
140 .decode = vcr1_decode_frame,
141 .capabilities = CODEC_CAP_DR1,