/* * TechSmith Camtasia decoder * Copyright (c) 2004 Konstantin Shishkov * * 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 */ /** * @file * TechSmith Camtasia decoder * * Fourcc: TSCC * * Codec is very simple: * it codes picture (picture difference, really) * with algorithm almost identical to Windows RLE8, * only without padding and with greater pixel sizes, * then this coded picture is packed with ZLib * * Supports: BGR8,BGR555,BGR24 - only BGR8 and BGR555 tested * */ #include <stdio.h> #include <stdlib.h> #include "avcodec.h" #include "msrledec.h" #include <zlib.h> /* * Decoder context */ typedef struct TsccContext { AVCodecContext *avctx; AVFrame pic; // Bits per pixel int bpp; // Decompressed data size unsigned int decomp_size; // Decompression buffer unsigned char* decomp_buf; int height; z_stream zstream; uint32_t pal[256]; } CamtasiaContext; /* * * Decode a frame * */ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt) { const uint8_t *buf = avpkt->data; int buf_size = avpkt->size; CamtasiaContext * const c = avctx->priv_data; const unsigned char *encoded = buf; int zret; // Zlib return code int len = buf_size; if(c->pic.data[0]) avctx->release_buffer(avctx, &c->pic); c->pic.reference = 3; c->pic.buffer_hints = FF_BUFFER_HINTS_VALID; if(avctx->get_buffer(avctx, &c->pic) < 0){ av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n"); return -1; } zret = inflateReset(&c->zstream); if (zret != Z_OK) { av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret); return -1; } c->zstream.next_in = encoded; c->zstream.avail_in = len; c->zstream.next_out = c->decomp_buf; c->zstream.avail_out = c->decomp_size; zret = inflate(&c->zstream, Z_FINISH); // Z_DATA_ERROR means empty picture if ((zret != Z_OK) && (zret != Z_STREAM_END) && (zret != Z_DATA_ERROR)) { av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", zret); return -1; } if(zret != Z_DATA_ERROR) ff_msrle_decode(avctx, (AVPicture*)&c->pic, c->bpp, c->decomp_buf, c->decomp_size - c->zstream.avail_out); /* make the palette available on the way out */ if (c->avctx->pix_fmt == PIX_FMT_PAL8) { const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, NULL); if (pal) { c->pic.palette_has_changed = 1; memcpy(c->pal, pal, AVPALETTE_SIZE); } memcpy(c->pic.data[1], c->pal, AVPALETTE_SIZE); } *data_size = sizeof(AVFrame); *(AVFrame*)data = c->pic; /* always report that the buffer was completely consumed */ return buf_size; } /* * * Init tscc decoder * */ static av_cold int decode_init(AVCodecContext *avctx) { CamtasiaContext * const c = avctx->priv_data; int zret; // Zlib return code c->avctx = avctx; c->height = avctx->height; avcodec_get_frame_defaults(&c->pic); // Needed if zlib unused or init aborted before inflateInit memset(&c->zstream, 0, sizeof(z_stream)); switch(avctx->bits_per_coded_sample){ case 8: avctx->pix_fmt = PIX_FMT_PAL8; break; 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, "Camtasia error: unknown depth %i bpp\n", avctx->bits_per_coded_sample); return -1; } c->bpp = avctx->bits_per_coded_sample; // buffer size for RLE 'best' case when 2-byte code precedes each pixel and there may be padding after it too c->decomp_size = (((avctx->width * c->bpp + 7) >> 3) + 3 * avctx->width + 2) * avctx->height + 2; /* Allocate decompression buffer */ if (c->decomp_size) { if ((c->decomp_buf = av_malloc(c->decomp_size)) == NULL) { av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n"); return 1; } } c->zstream.zalloc = Z_NULL; c->zstream.zfree = Z_NULL; c->zstream.opaque = Z_NULL; zret = inflateInit(&c->zstream); if (zret != Z_OK) { av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret); return 1; } return 0; } /* * * Uninit tscc decoder * */ static av_cold int decode_end(AVCodecContext *avctx) { CamtasiaContext * const c = avctx->priv_data; av_freep(&c->decomp_buf); if (c->pic.data[0]) avctx->release_buffer(avctx, &c->pic); inflateEnd(&c->zstream); return 0; } AVCodec ff_tscc_decoder = { .name = "camtasia", .type = AVMEDIA_TYPE_VIDEO, .id = CODEC_ID_TSCC, .priv_data_size = sizeof(CamtasiaContext), .init = decode_init, .close = decode_end, .decode = decode_frame, .capabilities = CODEC_CAP_DR1, .long_name = NULL_IF_CONFIG_SMALL("TechSmith Screen Capture Codec"), };