1/* 2 * Dxtory decoder 3 * 4 * Copyright (c) 2011 Konstantin Shishkov 5 * 6 * This file is part of Libav. 7 * 8 * Libav is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU Lesser General Public 10 * License as published by the Free Software Foundation; either 11 * version 2.1 of the License, or (at your option) any later version. 12 * 13 * Libav is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 16 * Lesser General Public License for more details. 17 * 18 * You should have received a copy of the GNU Lesser General Public 19 * License along with Libav; if not, write to the Free Software 20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 21 */ 22 23#include "avcodec.h" 24#include "libavutil/intreadwrite.h" 25 26static av_cold int decode_init(AVCodecContext *avctx) 27{ 28 avctx->pix_fmt = PIX_FMT_YUV420P; 29 avctx->coded_frame = avcodec_alloc_frame(); 30 if (!avctx->coded_frame) 31 return AVERROR(ENOMEM); 32 33 return 0; 34} 35 36static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, 37 AVPacket *avpkt) 38{ 39 int h, w; 40 AVFrame *pic = avctx->coded_frame; 41 const uint8_t *src = avpkt->data; 42 uint8_t *Y1, *Y2, *U, *V; 43 int ret; 44 45 if (pic->data[0]) 46 avctx->release_buffer(avctx, pic); 47 48 if (avpkt->size < avctx->width * avctx->height * 3 / 2 + 16) { 49 av_log(avctx, AV_LOG_ERROR, "packet too small\n"); 50 return AVERROR_INVALIDDATA; 51 } 52 53 pic->reference = 0; 54 if ((ret = avctx->get_buffer(avctx, pic)) < 0) 55 return ret; 56 57 pic->pict_type = AV_PICTURE_TYPE_I; 58 pic->key_frame = 1; 59 60 if (AV_RL32(src) != 0x01000002) { 61 av_log_ask_for_sample(avctx, "Unknown frame header %X\n", AV_RL32(src)); 62 return AVERROR_PATCHWELCOME; 63 } 64 src += 16; 65 66 Y1 = pic->data[0]; 67 Y2 = pic->data[0] + pic->linesize[0]; 68 U = pic->data[1]; 69 V = pic->data[2]; 70 for (h = 0; h < avctx->height; h += 2) { 71 for (w = 0; w < avctx->width; w += 2) { 72 AV_WN16A(Y1 + w, AV_RN16A(src)); 73 AV_WN16A(Y2 + w, AV_RN16A(src + 2)); 74 U[w >> 1] = src[4] + 0x80; 75 V[w >> 1] = src[5] + 0x80; 76 src += 6; 77 } 78 Y1 += pic->linesize[0] << 1; 79 Y2 += pic->linesize[0] << 1; 80 U += pic->linesize[1]; 81 V += pic->linesize[2]; 82 } 83 84 *data_size = sizeof(AVFrame); 85 *(AVFrame*)data = *pic; 86 87 return avpkt->size; 88} 89 90static av_cold int decode_close(AVCodecContext *avctx) 91{ 92 AVFrame *pic = avctx->coded_frame; 93 if (pic->data[0]) 94 avctx->release_buffer(avctx, pic); 95 av_freep(&avctx->coded_frame); 96 97 return 0; 98} 99 100AVCodec ff_dxtory_decoder = { 101 .name = "dxtory", 102 .long_name = NULL_IF_CONFIG_SMALL("Dxtory"), 103 .type = AVMEDIA_TYPE_VIDEO, 104 .id = CODEC_ID_DXTORY, 105 .init = decode_init, 106 .close = decode_close, 107 .decode = decode_frame, 108 .capabilities = CODEC_CAP_DR1, 109}; 110