3 * Copyright (c) 2006 Reimar Doeffinger
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
26 #include "libavutil/common.h"
31 #include "libavutil/lzo.h"
35 int linelen, height, bpp;
36 unsigned int decomp_size;
37 unsigned char* decomp_buf;
40 static void copy_frame_default(AVFrame *f, const uint8_t *src,
41 int linelen, int height) {
42 int i, src_stride = FFALIGN(linelen, 4);
43 uint8_t *dst = f->data[0];
44 dst += (height - 1) * f->linesize[0];
45 for (i = height; i; i--) {
46 memcpy(dst, src, linelen);
48 dst -= f->linesize[0];
52 static void add_frame_default(AVFrame *f, const uint8_t *src,
53 int linelen, int height) {
54 int i, j, src_stride = FFALIGN(linelen, 4);
55 uint8_t *dst = f->data[0];
56 dst += (height - 1) * f->linesize[0];
57 for (i = height; i; i--) {
58 for (j = linelen; j; j--)
60 src += src_stride - linelen;
61 dst -= f->linesize[0] + linelen;
65 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
67 const uint8_t *buf = avpkt->data;
68 int buf_size = avpkt->size;
69 CamStudioContext *c = avctx->priv_data;
70 AVFrame *picture = data;
74 av_log(avctx, AV_LOG_ERROR, "coded frame too small\n");
75 return AVERROR_INVALIDDATA;
79 c->pic.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_READABLE |
80 FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE;
81 if ((ret = avctx->reget_buffer(avctx, &c->pic)) < 0) {
82 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
87 switch ((buf[0] >> 1) & 7) {
88 case 0: { // lzo compression
89 int outlen = c->decomp_size, inlen = buf_size - 2;
90 if (av_lzo1x_decode(c->decomp_buf, &outlen, &buf[2], &inlen))
91 av_log(avctx, AV_LOG_ERROR, "error during lzo decompression\n");
94 case 1: { // zlib compression
96 unsigned long dlen = c->decomp_size;
97 if (uncompress(c->decomp_buf, &dlen, &buf[2], buf_size - 2) != Z_OK)
98 av_log(avctx, AV_LOG_ERROR, "error during zlib decompression\n");
101 av_log(avctx, AV_LOG_ERROR, "compiled without zlib support\n");
102 return AVERROR(ENOSYS);
106 av_log(avctx, AV_LOG_ERROR, "unknown compression\n");
107 return AVERROR_INVALIDDATA;
110 // flip upside down, add difference frame
111 if (buf[0] & 1) { // keyframe
112 c->pic.pict_type = AV_PICTURE_TYPE_I;
113 c->pic.key_frame = 1;
114 copy_frame_default(&c->pic, c->decomp_buf,
115 c->linelen, c->height);
117 c->pic.pict_type = AV_PICTURE_TYPE_P;
118 c->pic.key_frame = 0;
119 add_frame_default(&c->pic, c->decomp_buf,
120 c->linelen, c->height);
128 static av_cold int decode_init(AVCodecContext *avctx) {
129 CamStudioContext *c = avctx->priv_data;
131 switch (avctx->bits_per_coded_sample) {
132 case 16: avctx->pix_fmt = AV_PIX_FMT_RGB555LE; break;
133 case 24: avctx->pix_fmt = AV_PIX_FMT_BGR24; break;
134 case 32: avctx->pix_fmt = AV_PIX_FMT_BGRA; break;
136 av_log(avctx, AV_LOG_ERROR,
137 "CamStudio codec error: invalid depth %i bpp\n",
138 avctx->bits_per_coded_sample);
139 return AVERROR_INVALIDDATA;
141 c->bpp = avctx->bits_per_coded_sample;
142 avcodec_get_frame_defaults(&c->pic);
143 c->pic.data[0] = NULL;
144 c->linelen = avctx->width * avctx->bits_per_coded_sample / 8;
145 c->height = avctx->height;
146 stride = FFALIGN(c->linelen, 4);
147 c->decomp_size = c->height * stride;
148 c->decomp_buf = av_malloc(c->decomp_size + AV_LZO_OUTPUT_PADDING);
149 if (!c->decomp_buf) {
150 av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
151 return AVERROR(ENOMEM);
156 static av_cold int decode_end(AVCodecContext *avctx) {
157 CamStudioContext *c = avctx->priv_data;
158 av_freep(&c->decomp_buf);
160 avctx->release_buffer(avctx, &c->pic);
164 AVCodec ff_cscd_decoder = {
166 .type = AVMEDIA_TYPE_VIDEO,
167 .id = AV_CODEC_ID_CSCD,
168 .priv_data_size = sizeof(CamStudioContext),
171 .decode = decode_frame,
172 .capabilities = CODEC_CAP_DR1,
173 .long_name = NULL_IF_CONFIG_SMALL("CamStudio"),