1/* 2 * TechSmith Camtasia decoder 3 * Copyright (c) 2004 Konstantin Shishkov 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 * TechSmith Camtasia decoder 25 * 26 * Fourcc: TSCC 27 * 28 * Codec is very simple: 29 * it codes picture (picture difference, really) 30 * with algorithm almost identical to Windows RLE8, 31 * only without padding and with greater pixel sizes, 32 * then this coded picture is packed with ZLib 33 * 34 * Supports: BGR8,BGR555,BGR24 - only BGR8 and BGR555 tested 35 * 36 */ 37 38#include <stdio.h> 39#include <stdlib.h> 40 41#include "avcodec.h" 42#include "internal.h" 43#include "msrledec.h" 44 45#include <zlib.h> 46 47typedef struct TsccContext { 48 49 AVCodecContext *avctx; 50 AVFrame *frame; 51 52 // Bits per pixel 53 int bpp; 54 // Decompressed data size 55 unsigned int decomp_size; 56 // Decompression buffer 57 unsigned char* decomp_buf; 58 GetByteContext gb; 59 int height; 60 z_stream zstream; 61 62 uint32_t pal[256]; 63} CamtasiaContext; 64 65static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, 66 AVPacket *avpkt) 67{ 68 const uint8_t *buf = avpkt->data; 69 int buf_size = avpkt->size; 70 CamtasiaContext * const c = avctx->priv_data; 71 const unsigned char *encoded = buf; 72 AVFrame *frame = c->frame; 73 int zret; // Zlib return code 74 int ret, len = buf_size; 75 76 if ((ret = ff_reget_buffer(avctx, frame)) < 0) 77 return ret; 78 79 zret = inflateReset(&c->zstream); 80 if (zret != Z_OK) { 81 av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret); 82 return AVERROR_UNKNOWN; 83 } 84 c->zstream.next_in = (uint8_t*)encoded; 85 c->zstream.avail_in = len; 86 c->zstream.next_out = c->decomp_buf; 87 c->zstream.avail_out = c->decomp_size; 88 zret = inflate(&c->zstream, Z_FINISH); 89 // Z_DATA_ERROR means empty picture 90 if ((zret != Z_OK) && (zret != Z_STREAM_END) && (zret != Z_DATA_ERROR)) { 91 av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", zret); 92 return AVERROR_UNKNOWN; 93 } 94 95 96 if (zret != Z_DATA_ERROR) { 97 bytestream2_init(&c->gb, c->decomp_buf, 98 c->decomp_size - c->zstream.avail_out); 99 ff_msrle_decode(avctx, (AVPicture*)frame, c->bpp, &c->gb); 100 } 101 102 /* make the palette available on the way out */ 103 if (c->avctx->pix_fmt == AV_PIX_FMT_PAL8) { 104 const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, NULL); 105 106 if (pal) { 107 frame->palette_has_changed = 1; 108 memcpy(c->pal, pal, AVPALETTE_SIZE); 109 } 110 memcpy(frame->data[1], c->pal, AVPALETTE_SIZE); 111 } 112 113 if ((ret = av_frame_ref(data, frame)) < 0) 114 return ret; 115 *got_frame = 1; 116 117 /* always report that the buffer was completely consumed */ 118 return buf_size; 119} 120 121static av_cold int decode_init(AVCodecContext *avctx) 122{ 123 CamtasiaContext * const c = avctx->priv_data; 124 int zret; // Zlib return code 125 126 c->avctx = avctx; 127 128 c->height = avctx->height; 129 130 // Needed if zlib unused or init aborted before inflateInit 131 memset(&c->zstream, 0, sizeof(z_stream)); 132 switch(avctx->bits_per_coded_sample){ 133 case 8: avctx->pix_fmt = AV_PIX_FMT_PAL8; break; 134 case 16: avctx->pix_fmt = AV_PIX_FMT_RGB555; break; 135 case 24: 136 avctx->pix_fmt = AV_PIX_FMT_BGR24; 137 break; 138 case 32: avctx->pix_fmt = AV_PIX_FMT_RGB32; break; 139 default: av_log(avctx, AV_LOG_ERROR, "Camtasia error: unknown depth %i bpp\n", avctx->bits_per_coded_sample); 140 return AVERROR_PATCHWELCOME; 141 } 142 c->bpp = avctx->bits_per_coded_sample; 143 // buffer size for RLE 'best' case when 2-byte code precedes each pixel and there may be padding after it too 144 c->decomp_size = (((avctx->width * c->bpp + 7) >> 3) + 3 * avctx->width + 2) * avctx->height + 2; 145 146 /* Allocate decompression buffer */ 147 if (c->decomp_size) { 148 if ((c->decomp_buf = av_malloc(c->decomp_size)) == NULL) { 149 av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n"); 150 return AVERROR(ENOMEM); 151 } 152 } 153 154 c->zstream.zalloc = Z_NULL; 155 c->zstream.zfree = Z_NULL; 156 c->zstream.opaque = Z_NULL; 157 zret = inflateInit(&c->zstream); 158 if (zret != Z_OK) { 159 av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret); 160 return AVERROR_UNKNOWN; 161 } 162 163 c->frame = av_frame_alloc(); 164 165 return 0; 166} 167 168static av_cold int decode_end(AVCodecContext *avctx) 169{ 170 CamtasiaContext * const c = avctx->priv_data; 171 172 av_freep(&c->decomp_buf); 173 av_frame_free(&c->frame); 174 175 inflateEnd(&c->zstream); 176 177 return 0; 178} 179 180AVCodec ff_tscc_decoder = { 181 .name = "camtasia", 182 .long_name = NULL_IF_CONFIG_SMALL("TechSmith Screen Capture Codec"), 183 .type = AVMEDIA_TYPE_VIDEO, 184 .id = AV_CODEC_ID_TSCC, 185 .priv_data_size = sizeof(CamtasiaContext), 186 .init = decode_init, 187 .close = decode_end, 188 .decode = decode_frame, 189 .capabilities = CODEC_CAP_DR1, 190}; 191