/* * CamStudio decoder * Copyright (c) 2006 Reimar Doeffinger * * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include <stdio.h> #include <stdlib.h> #include "avcodec.h" #ifdef CONFIG_ZLIB #include <zlib.h> #endif #include "lzo.h" typedef struct { AVFrame pic; int linelen, height, bpp; unsigned int decomp_size; unsigned char* decomp_buf; } CamStudioContext; static void copy_frame_default(AVFrame *f, const uint8_t *src, int linelen, int height) { int i; uint8_t *dst = f->data[0]; dst += (height - 1) * f->linesize[0]; for (i = height; i; i--) { memcpy(dst, src, linelen); src += linelen; dst -= f->linesize[0]; } } static void add_frame_default(AVFrame *f, const uint8_t *src, int linelen, int height) { int i, j; uint8_t *dst = f->data[0]; dst += (height - 1) * f->linesize[0]; for (i = height; i; i--) { for (j = linelen; j; j--) *dst++ += *src++; dst -= f->linesize[0] + linelen; } } #ifndef WORDS_BIGENDIAN #define copy_frame_16 copy_frame_default #define copy_frame_32 copy_frame_default #define add_frame_16 add_frame_default #define add_frame_32 add_frame_default #else static void copy_frame_16(AVFrame *f, const uint8_t *src, int linelen, int height) { int i, j; uint8_t *dst = f->data[0]; dst += (height - 1) * f->linesize[0]; for (i = height; i; i--) { for (j = linelen / 2; j; j--) { dst[0] = src[1]; dst[1] = src[0]; src += 2; dst += 2; } dst -= f->linesize[0] + linelen; } } static void copy_frame_32(AVFrame *f, const uint8_t *src, int linelen, int height) { int i, j; uint8_t *dst = f->data[0]; dst += (height - 1) * f->linesize[0]; for (i = height; i; i--) { for (j = linelen / 4; j; j--) { dst[0] = src[3]; dst[1] = src[2]; dst[2] = src[1]; dst[3] = src[0]; src += 4; dst += 4; } dst -= f->linesize[0] + linelen; } } static void add_frame_16(AVFrame *f, const uint8_t *src, int linelen, int height) { int i, j; uint8_t *dst = f->data[0]; dst += (height - 1) * f->linesize[0]; for (i = height; i; i--) { for (j = linelen / 2; j; j--) { dst[0] += src[1]; dst[1] += src[0]; src += 2; dst += 2; } dst -= f->linesize[0] + linelen; } } static void add_frame_32(AVFrame *f, const uint8_t *src, int linelen, int height) { int i, j; uint8_t *dst = f->data[0]; dst += (height - 1) * f->linesize[0]; for (i = height; i; i--) { for (j = linelen / 4; j; j--) { dst[0] += src[3]; dst[1] += src[2]; dst[2] += src[1]; dst[3] += src[0]; src += 4; dst += 4; } dst -= f->linesize[0] + linelen; } } #endif static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, const uint8_t *buf, int buf_size) { CamStudioContext *c = avctx->priv_data; AVFrame *picture = data; if (buf_size < 2) { av_log(avctx, AV_LOG_ERROR, "coded frame too small\n"); return -1; } if (c->pic.data[0]) avctx->release_buffer(avctx, &c->pic); c->pic.reference = 1; c->pic.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_READABLE | FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE; if (avctx->get_buffer(avctx, &c->pic) < 0) { av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n"); return -1; } // decompress data switch ((buf[0] >> 1) & 7) { case 0: { // lzo compression int outlen = c->decomp_size, inlen = buf_size - 2; if (lzo1x_decode(c->decomp_buf, &outlen, &buf[2], &inlen)) av_log(avctx, AV_LOG_ERROR, "error during lzo decompression\n"); break; } case 1: { // zlib compression #ifdef CONFIG_ZLIB unsigned long dlen = c->decomp_size; if (uncompress(c->decomp_buf, &dlen, &buf[2], buf_size - 2) != Z_OK) av_log(avctx, AV_LOG_ERROR, "error during zlib decompression\n"); break; #else av_log(avctx, AV_LOG_ERROR, "compiled without zlib support\n"); return -1; #endif } default: av_log(avctx, AV_LOG_ERROR, "unknown compression\n"); return -1; } // flip upside down, add difference frame if (buf[0] & 1) { // keyframe c->pic.pict_type = FF_I_TYPE; c->pic.key_frame = 1; switch (c->bpp) { case 16: copy_frame_16(&c->pic, c->decomp_buf, c->linelen, c->height); break; case 32: copy_frame_32(&c->pic, c->decomp_buf, c->linelen, c->height); break; default: copy_frame_default(&c->pic, c->decomp_buf, c->linelen, c->height); } } else { c->pic.pict_type = FF_P_TYPE; c->pic.key_frame = 0; switch (c->bpp) { case 16: add_frame_16(&c->pic, c->decomp_buf, c->linelen, c->height); break; case 32: add_frame_32(&c->pic, c->decomp_buf, c->linelen, c->height); break; default: add_frame_default(&c->pic, c->decomp_buf, c->linelen, c->height); } } *picture = c->pic; *data_size = sizeof(AVFrame); return buf_size; } static int decode_init(AVCodecContext *avctx) { CamStudioContext *c = avctx->priv_data; if (avcodec_check_dimensions(avctx, avctx->height, avctx->width) < 0) { return 1; } switch (avctx->bits_per_sample) { case 16: avctx->pix_fmt = PIX_FMT_RGB555; break; case 24: avctx->pix_fmt = PIX_FMT_BGR24; break; case 32: avctx->pix_fmt = PIX_FMT_RGB32; break; default: av_log(avctx, AV_LOG_ERROR, "CamStudio codec error: invalid depth %i bpp\n", avctx->bits_per_sample); return 1; } c->bpp = avctx->bits_per_sample; c->pic.data[0] = NULL; c->linelen = avctx->width * avctx->bits_per_sample / 8; c->height = avctx->height; c->decomp_size = c->height * c->linelen; c->decomp_buf = av_malloc(c->decomp_size + LZO_OUTPUT_PADDING); if (!c->decomp_buf) { av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n"); return 1; } return 0; } static int decode_end(AVCodecContext *avctx) { CamStudioContext *c = avctx->priv_data; av_freep(&c->decomp_buf); if (c->pic.data[0]) avctx->release_buffer(avctx, &c->pic); return 0; } AVCodec cscd_decoder = { "camstudio", CODEC_TYPE_VIDEO, CODEC_ID_CSCD, sizeof(CamStudioContext), decode_init, NULL, decode_end, decode_frame, CODEC_CAP_DR1, };