2 * TechSmith Camtasia decoder
3 * Copyright (c) 2004 Konstantin Shishkov
5 * This file is part of FFmpeg.
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.
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.
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
24 * TechSmith Camtasia decoder
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
34 * Supports: BGR8,BGR555,BGR24 - only BGR8 and BGR555 tested
50 typedef struct TsccContext {
52 AVCodecContext *avctx;
57 // Decompressed data size
58 unsigned int decomp_size;
59 // Decompression buffer
60 unsigned char* decomp_buf;
70 static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt)
72 const uint8_t *buf = avpkt->data;
73 int buf_size = avpkt->size;
74 CamtasiaContext * const c = avctx->priv_data;
75 const unsigned char *encoded = buf;
76 unsigned char *outptr;
77 int zret; // Zlib return code
81 avctx->release_buffer(avctx, &c->pic);
84 c->pic.buffer_hints = FF_BUFFER_HINTS_VALID;
85 if(avctx->get_buffer(avctx, &c->pic) < 0){
86 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
90 outptr = c->pic.data[0]; // Output image pointer
92 zret = inflateReset(&(c->zstream));
94 av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);
97 c->zstream.next_in = encoded;
98 c->zstream.avail_in = len;
99 c->zstream.next_out = c->decomp_buf;
100 c->zstream.avail_out = c->decomp_size;
101 zret = inflate(&(c->zstream), Z_FINISH);
102 // Z_DATA_ERROR means empty picture
103 if ((zret != Z_OK) && (zret != Z_STREAM_END) && (zret != Z_DATA_ERROR)) {
104 av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", zret);
109 if(zret != Z_DATA_ERROR)
110 ff_msrle_decode(avctx, (AVPicture*)&c->pic, c->bpp, c->decomp_buf, c->decomp_size - c->zstream.avail_out);
112 /* make the palette available on the way out */
113 if (c->avctx->pix_fmt == PIX_FMT_PAL8) {
114 memcpy(c->pic.data[1], c->avctx->palctrl->palette, AVPALETTE_SIZE);
115 if (c->avctx->palctrl->palette_changed) {
116 c->pic.palette_has_changed = 1;
117 c->avctx->palctrl->palette_changed = 0;
121 *data_size = sizeof(AVFrame);
122 *(AVFrame*)data = c->pic;
124 /* always report that the buffer was completely consumed */
135 static av_cold int decode_init(AVCodecContext *avctx)
137 CamtasiaContext * const c = avctx->priv_data;
138 int zret; // Zlib return code
142 c->height = avctx->height;
144 // Needed if zlib unused or init aborted before inflateInit
145 memset(&(c->zstream), 0, sizeof(z_stream));
146 switch(avctx->bits_per_coded_sample){
147 case 8: avctx->pix_fmt = PIX_FMT_PAL8; break;
148 case 16: avctx->pix_fmt = PIX_FMT_RGB555; break;
150 avctx->pix_fmt = PIX_FMT_BGR24;
152 case 32: avctx->pix_fmt = PIX_FMT_RGB32; break;
153 default: av_log(avctx, AV_LOG_ERROR, "Camtasia error: unknown depth %i bpp\n", avctx->bits_per_coded_sample);
156 c->bpp = avctx->bits_per_coded_sample;
157 // buffer size for RLE 'best' case when 2-byte code preceeds each pixel and there may be padding after it too
158 c->decomp_size = (((avctx->width * c->bpp + 7) >> 3) + 3 * avctx->width + 2) * avctx->height + 2;
160 /* Allocate decompression buffer */
161 if (c->decomp_size) {
162 if ((c->decomp_buf = av_malloc(c->decomp_size)) == NULL) {
163 av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
168 c->zstream.zalloc = Z_NULL;
169 c->zstream.zfree = Z_NULL;
170 c->zstream.opaque = Z_NULL;
171 zret = inflateInit(&(c->zstream));
173 av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
184 * Uninit tscc decoder
187 static av_cold int decode_end(AVCodecContext *avctx)
189 CamtasiaContext * const c = avctx->priv_data;
191 av_freep(&c->decomp_buf);
194 avctx->release_buffer(avctx, &c->pic);
195 inflateEnd(&(c->zstream));
200 AVCodec ff_tscc_decoder = {
204 sizeof(CamtasiaContext),
210 .long_name = NULL_IF_CONFIG_SMALL("TechSmith Screen Capture Codec"),