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 #include <stdio.h>
38 #include <stdlib.h>
39
40 #include "avcodec.h"
41 #include "codec_internal.h"
42 #include "decode.h"
43 #include "internal.h"
44 #include "msrledec.h"
45 #include "zlib_wrapper.h"
46
47 #include <zlib.h>
48
49 typedef struct TsccContext {
50
51 AVCodecContext *avctx;
52 AVFrame *frame;
53
54 // Bits per pixel
55 int bpp;
56 // Decompressed data size
57 unsigned int decomp_size;
58 // Decompression buffer
59 unsigned char* decomp_buf;
60 GetByteContext gb;
61 int height;
62 FFZStream zstream;
63
64 uint32_t pal[256];
65 } CamtasiaContext;
66
decode_frame(AVCodecContext *avctx, AVFrame *rframe, int *got_frame, AVPacket *avpkt)67 static int decode_frame(AVCodecContext *avctx, AVFrame *rframe,
68 int *got_frame, AVPacket *avpkt)
69 {
70 const uint8_t *buf = avpkt->data;
71 int buf_size = avpkt->size;
72 CamtasiaContext * const c = avctx->priv_data;
73 z_stream *const zstream = &c->zstream.zstream;
74 AVFrame *frame = c->frame;
75 int ret;
76 int palette_has_changed = 0;
77
78 if (c->avctx->pix_fmt == AV_PIX_FMT_PAL8) {
79 palette_has_changed = ff_copy_palette(c->pal, avpkt, avctx);
80 }
81
82 ret = inflateReset(zstream);
83 if (ret != Z_OK) {
84 av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
85 return AVERROR_UNKNOWN;
86 }
87 zstream->next_in = buf;
88 zstream->avail_in = buf_size;
89 zstream->next_out = c->decomp_buf;
90 zstream->avail_out = c->decomp_size;
91 ret = inflate(zstream, Z_FINISH);
92 // Z_DATA_ERROR means empty picture
93 if (ret == Z_DATA_ERROR && !palette_has_changed) {
94 return buf_size;
95 }
96
97 if ((ret != Z_OK) && (ret != Z_STREAM_END) && (ret != Z_DATA_ERROR)) {
98 av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", ret);
99 return AVERROR_UNKNOWN;
100 }
101
102 if ((ret = ff_reget_buffer(avctx, frame, 0)) < 0)
103 return ret;
104
105 if (ret != Z_DATA_ERROR) {
106 bytestream2_init(&c->gb, c->decomp_buf,
107 c->decomp_size - zstream->avail_out);
108 ff_msrle_decode(avctx, frame, c->bpp, &c->gb);
109 }
110
111 /* make the palette available on the way out */
112 if (c->avctx->pix_fmt == AV_PIX_FMT_PAL8) {
113 frame->palette_has_changed = palette_has_changed;
114 memcpy(frame->data[1], c->pal, AVPALETTE_SIZE);
115 }
116
117 if ((ret = av_frame_ref(rframe, frame)) < 0)
118 return ret;
119 *got_frame = 1;
120
121 /* always report that the buffer was completely consumed */
122 return buf_size;
123 }
124
decode_init(AVCodecContext *avctx)125 static av_cold int decode_init(AVCodecContext *avctx)
126 {
127 CamtasiaContext * const c = avctx->priv_data;
128
129 c->avctx = avctx;
130
131 c->height = avctx->height;
132
133 switch(avctx->bits_per_coded_sample){
134 case 8: avctx->pix_fmt = AV_PIX_FMT_PAL8; break;
135 case 16: avctx->pix_fmt = AV_PIX_FMT_RGB555; break;
136 case 24:
137 avctx->pix_fmt = AV_PIX_FMT_BGR24;
138 break;
139 case 32: avctx->pix_fmt = AV_PIX_FMT_0RGB32; break;
140 default: av_log(avctx, AV_LOG_ERROR, "Camtasia error: unknown depth %i bpp\n", avctx->bits_per_coded_sample);
141 return AVERROR_PATCHWELCOME;
142 }
143 c->bpp = avctx->bits_per_coded_sample;
144 // buffer size for RLE 'best' case when 2-byte code precedes each pixel and there may be padding after it too
145 c->decomp_size = (((avctx->width * c->bpp + 7) >> 3) + 3 * avctx->width + 2) * avctx->height + 2;
146
147 /* Allocate decompression buffer */
148 if (c->decomp_size) {
149 if (!(c->decomp_buf = av_malloc(c->decomp_size))) {
150 av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
151 return AVERROR(ENOMEM);
152 }
153 }
154
155 c->frame = av_frame_alloc();
156 if (!c->frame)
157 return AVERROR(ENOMEM);
158
159 return ff_inflate_init(&c->zstream, avctx);
160 }
161
decode_end(AVCodecContext *avctx)162 static av_cold int decode_end(AVCodecContext *avctx)
163 {
164 CamtasiaContext * const c = avctx->priv_data;
165
166 av_freep(&c->decomp_buf);
167 av_frame_free(&c->frame);
168 ff_inflate_end(&c->zstream);
169
170 return 0;
171 }
172
173 const FFCodec ff_tscc_decoder = {
174 .p.name = "camtasia",
175 .p.long_name = NULL_IF_CONFIG_SMALL("TechSmith Screen Capture Codec"),
176 .p.type = AVMEDIA_TYPE_VIDEO,
177 .p.id = AV_CODEC_ID_TSCC,
178 .priv_data_size = sizeof(CamtasiaContext),
179 .init = decode_init,
180 .close = decode_end,
181 FF_CODEC_DECODE_CB(decode_frame),
182 .p.capabilities = AV_CODEC_CAP_DR1,
183 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP,
184 };
185