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 "codec_internal.h" 29#include "internal.h" 30#include "libavutil/avassert.h" 31#include "libavutil/internal.h" 32 33typedef struct VCR1Context { 34 int delta[16]; 35 int offset[4]; 36} VCR1Context; 37 38static av_cold int vcr1_decode_init(AVCodecContext *avctx) 39{ 40 avctx->pix_fmt = AV_PIX_FMT_YUV410P; 41 42 if (avctx->width % 8 || avctx->height%4) { 43 avpriv_request_sample(avctx, "odd dimensions (%d x %d) support", avctx->width, avctx->height); 44 return AVERROR_INVALIDDATA; 45 } 46 47 return 0; 48} 49 50static int vcr1_decode_frame(AVCodecContext *avctx, AVFrame *p, 51 int *got_frame, AVPacket *avpkt) 52{ 53 VCR1Context *const a = avctx->priv_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 124const FFCodec ff_vcr1_decoder = { 125 .p.name = "vcr1", 126 .p.long_name = NULL_IF_CONFIG_SMALL("ATI VCR1"), 127 .p.type = AVMEDIA_TYPE_VIDEO, 128 .p.id = AV_CODEC_ID_VCR1, 129 .priv_data_size = sizeof(VCR1Context), 130 .init = vcr1_decode_init, 131 FF_CODEC_DECODE_CB(vcr1_decode_frame), 132 .p.capabilities = AV_CODEC_CAP_DR1, 133 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE, 134}; 135