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 libavcodec/tscc.c 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 "msrledec.h" 43 44#include <zlib.h> 45 46 47/* 48 * Decoder context 49 */ 50typedef struct TsccContext { 51 52 AVCodecContext *avctx; 53 AVFrame pic; 54 55 // Bits per pixel 56 int bpp; 57 // Decompressed data size 58 unsigned int decomp_size; 59 // Decompression buffer 60 unsigned char* decomp_buf; 61 int height; 62 z_stream zstream; 63} CamtasiaContext; 64 65/* 66 * 67 * Decode a frame 68 * 69 */ 70static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, const uint8_t *buf, int buf_size) 71{ 72 CamtasiaContext * const c = avctx->priv_data; 73 const unsigned char *encoded = buf; 74 unsigned char *outptr; 75 int zret; // Zlib return code 76 int len = buf_size; 77 78 if(c->pic.data[0]) 79 avctx->release_buffer(avctx, &c->pic); 80 81 c->pic.reference = 1; 82 c->pic.buffer_hints = FF_BUFFER_HINTS_VALID; 83 if(avctx->get_buffer(avctx, &c->pic) < 0){ 84 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n"); 85 return -1; 86 } 87 88 outptr = c->pic.data[0]; // Output image pointer 89 90 zret = inflateReset(&(c->zstream)); 91 if (zret != Z_OK) { 92 av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret); 93 return -1; 94 } 95 c->zstream.next_in = encoded; 96 c->zstream.avail_in = len; 97 c->zstream.next_out = c->decomp_buf; 98 c->zstream.avail_out = c->decomp_size; 99 zret = inflate(&(c->zstream), Z_FINISH); 100 // Z_DATA_ERROR means empty picture 101 if ((zret != Z_OK) && (zret != Z_STREAM_END) && (zret != Z_DATA_ERROR)) { 102 av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", zret); 103 return -1; 104 } 105 106 107 if(zret != Z_DATA_ERROR) 108 ff_msrle_decode(avctx, (AVPicture*)&c->pic, c->bpp, c->decomp_buf, c->zstream.avail_out); 109 110 /* make the palette available on the way out */ 111 if (c->avctx->pix_fmt == PIX_FMT_PAL8) { 112 memcpy(c->pic.data[1], c->avctx->palctrl->palette, AVPALETTE_SIZE); 113 if (c->avctx->palctrl->palette_changed) { 114 c->pic.palette_has_changed = 1; 115 c->avctx->palctrl->palette_changed = 0; 116 } 117 } 118 119 *data_size = sizeof(AVFrame); 120 *(AVFrame*)data = c->pic; 121 122 /* always report that the buffer was completely consumed */ 123 return buf_size; 124} 125 126 127 128/* 129 * 130 * Init tscc decoder 131 * 132 */ 133static av_cold int decode_init(AVCodecContext *avctx) 134{ 135 CamtasiaContext * const c = avctx->priv_data; 136 int zret; // Zlib return code 137 138 c->avctx = avctx; 139 140 c->pic.data[0] = NULL; 141 c->height = avctx->height; 142 143 if (avcodec_check_dimensions(avctx, avctx->width, avctx->height) < 0) { 144 return 1; 145 } 146 147 // Needed if zlib unused or init aborted before inflateInit 148 memset(&(c->zstream), 0, sizeof(z_stream)); 149 switch(avctx->bits_per_coded_sample){ 150 case 8: avctx->pix_fmt = PIX_FMT_PAL8; break; 151 case 16: avctx->pix_fmt = PIX_FMT_RGB555; break; 152 case 24: 153 avctx->pix_fmt = PIX_FMT_BGR24; 154 break; 155 case 32: avctx->pix_fmt = PIX_FMT_RGB32; break; 156 default: av_log(avctx, AV_LOG_ERROR, "Camtasia error: unknown depth %i bpp\n", avctx->bits_per_coded_sample); 157 return -1; 158 } 159 c->bpp = avctx->bits_per_coded_sample; 160 c->decomp_size = (avctx->width * c->bpp + (avctx->width + 254) / 255 + 2) * avctx->height + 2;//RLE in the 'best' case 161 162 /* Allocate decompression buffer */ 163 if (c->decomp_size) { 164 if ((c->decomp_buf = av_malloc(c->decomp_size)) == NULL) { 165 av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n"); 166 return 1; 167 } 168 } 169 170 c->zstream.zalloc = Z_NULL; 171 c->zstream.zfree = Z_NULL; 172 c->zstream.opaque = Z_NULL; 173 zret = inflateInit(&(c->zstream)); 174 if (zret != Z_OK) { 175 av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret); 176 return 1; 177 } 178 179 return 0; 180} 181 182 183 184/* 185 * 186 * Uninit tscc decoder 187 * 188 */ 189static av_cold int decode_end(AVCodecContext *avctx) 190{ 191 CamtasiaContext * const c = avctx->priv_data; 192 193 av_freep(&c->decomp_buf); 194 195 if (c->pic.data[0]) 196 avctx->release_buffer(avctx, &c->pic); 197 inflateEnd(&(c->zstream)); 198 199 return 0; 200} 201 202AVCodec tscc_decoder = { 203 "camtasia", 204 CODEC_TYPE_VIDEO, 205 CODEC_ID_TSCC, 206 sizeof(CamtasiaContext), 207 decode_init, 208 NULL, 209 decode_end, 210 decode_frame, 211 CODEC_CAP_DR1, 212 .long_name = NULL_IF_CONFIG_SMALL("TechSmith Screen Capture Codec"), 213}; 214 215