yading@10: /*
yading@10:  * TechSmith Camtasia decoder
yading@10:  * Copyright (c) 2004 Konstantin Shishkov
yading@10:  *
yading@10:  * This file is part of FFmpeg.
yading@10:  *
yading@10:  * FFmpeg is free software; you can redistribute it and/or
yading@10:  * modify it under the terms of the GNU Lesser General Public
yading@10:  * License as published by the Free Software Foundation; either
yading@10:  * version 2.1 of the License, or (at your option) any later version.
yading@10:  *
yading@10:  * FFmpeg is distributed in the hope that it will be useful,
yading@10:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@10:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@10:  * Lesser General Public License for more details.
yading@10:  *
yading@10:  * You should have received a copy of the GNU Lesser General Public
yading@10:  * License along with FFmpeg; if not, write to the Free Software
yading@10:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@10:  */
yading@10: 
yading@10: /**
yading@10:  * @file
yading@10:  * TechSmith Camtasia decoder
yading@10:  *
yading@10:  * Fourcc: TSCC
yading@10:  *
yading@10:  * Codec is very simple:
yading@10:  *  it codes picture (picture difference, really)
yading@10:  *  with algorithm almost identical to Windows RLE8,
yading@10:  *  only without padding and with greater pixel sizes,
yading@10:  *  then this coded picture is packed with ZLib
yading@10:  *
yading@10:  * Supports: BGR8,BGR555,BGR24 - only BGR8 and BGR555 tested
yading@10:  *
yading@10:  */
yading@10: 
yading@10: #include <stdio.h>
yading@10: #include <stdlib.h>
yading@10: 
yading@10: #include "avcodec.h"
yading@10: #include "internal.h"
yading@10: #include "msrledec.h"
yading@10: 
yading@10: #include <zlib.h>
yading@10: 
yading@10: typedef struct TsccContext {
yading@10: 
yading@10:     AVCodecContext *avctx;
yading@10:     AVFrame *frame;
yading@10: 
yading@10:     // Bits per pixel
yading@10:     int bpp;
yading@10:     // Decompressed data size
yading@10:     unsigned int decomp_size;
yading@10:     // Decompression buffer
yading@10:     unsigned char* decomp_buf;
yading@10:     GetByteContext gb;
yading@10:     int height;
yading@10:     z_stream zstream;
yading@10: 
yading@10:     uint32_t pal[256];
yading@10: } CamtasiaContext;
yading@10: 
yading@10: static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
yading@10:                         AVPacket *avpkt)
yading@10: {
yading@10:     const uint8_t *buf = avpkt->data;
yading@10:     int buf_size = avpkt->size;
yading@10:     CamtasiaContext * const c = avctx->priv_data;
yading@10:     const unsigned char *encoded = buf;
yading@10:     AVFrame *frame = c->frame;
yading@10:     int zret; // Zlib return code
yading@10:     int ret, len = buf_size;
yading@10: 
yading@10:     if ((ret = ff_reget_buffer(avctx, frame)) < 0)
yading@10:         return ret;
yading@10: 
yading@10:     zret = inflateReset(&c->zstream);
yading@10:     if (zret != Z_OK) {
yading@10:         av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);
yading@10:         return AVERROR_UNKNOWN;
yading@10:     }
yading@10:     c->zstream.next_in = (uint8_t*)encoded;
yading@10:     c->zstream.avail_in = len;
yading@10:     c->zstream.next_out = c->decomp_buf;
yading@10:     c->zstream.avail_out = c->decomp_size;
yading@10:     zret = inflate(&c->zstream, Z_FINISH);
yading@10:     // Z_DATA_ERROR means empty picture
yading@10:     if ((zret != Z_OK) && (zret != Z_STREAM_END) && (zret != Z_DATA_ERROR)) {
yading@10:         av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", zret);
yading@10:         return AVERROR_UNKNOWN;
yading@10:     }
yading@10: 
yading@10: 
yading@10:     if (zret != Z_DATA_ERROR) {
yading@10:         bytestream2_init(&c->gb, c->decomp_buf,
yading@10:                          c->decomp_size - c->zstream.avail_out);
yading@10:         ff_msrle_decode(avctx, (AVPicture*)frame, c->bpp, &c->gb);
yading@10:     }
yading@10: 
yading@10:     /* make the palette available on the way out */
yading@10:     if (c->avctx->pix_fmt == AV_PIX_FMT_PAL8) {
yading@10:         const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, NULL);
yading@10: 
yading@10:         if (pal) {
yading@10:             frame->palette_has_changed = 1;
yading@10:             memcpy(c->pal, pal, AVPALETTE_SIZE);
yading@10:         }
yading@10:         memcpy(frame->data[1], c->pal, AVPALETTE_SIZE);
yading@10:     }
yading@10: 
yading@10:     if ((ret = av_frame_ref(data, frame)) < 0)
yading@10:         return ret;
yading@10:     *got_frame      = 1;
yading@10: 
yading@10:     /* always report that the buffer was completely consumed */
yading@10:     return buf_size;
yading@10: }
yading@10: 
yading@10: static av_cold int decode_init(AVCodecContext *avctx)
yading@10: {
yading@10:     CamtasiaContext * const c = avctx->priv_data;
yading@10:     int zret; // Zlib return code
yading@10: 
yading@10:     c->avctx = avctx;
yading@10: 
yading@10:     c->height = avctx->height;
yading@10: 
yading@10:     // Needed if zlib unused or init aborted before inflateInit
yading@10:     memset(&c->zstream, 0, sizeof(z_stream));
yading@10:     switch(avctx->bits_per_coded_sample){
yading@10:     case  8: avctx->pix_fmt = AV_PIX_FMT_PAL8; break;
yading@10:     case 16: avctx->pix_fmt = AV_PIX_FMT_RGB555; break;
yading@10:     case 24:
yading@10:              avctx->pix_fmt = AV_PIX_FMT_BGR24;
yading@10:              break;
yading@10:     case 32: avctx->pix_fmt = AV_PIX_FMT_RGB32; break;
yading@10:     default: av_log(avctx, AV_LOG_ERROR, "Camtasia error: unknown depth %i bpp\n", avctx->bits_per_coded_sample);
yading@10:              return AVERROR_PATCHWELCOME;
yading@10:     }
yading@10:     c->bpp = avctx->bits_per_coded_sample;
yading@10:     // buffer size for RLE 'best' case when 2-byte code precedes each pixel and there may be padding after it too
yading@10:     c->decomp_size = (((avctx->width * c->bpp + 7) >> 3) + 3 * avctx->width + 2) * avctx->height + 2;
yading@10: 
yading@10:     /* Allocate decompression buffer */
yading@10:     if (c->decomp_size) {
yading@10:         if ((c->decomp_buf = av_malloc(c->decomp_size)) == NULL) {
yading@10:             av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
yading@10:             return AVERROR(ENOMEM);
yading@10:         }
yading@10:     }
yading@10: 
yading@10:     c->zstream.zalloc = Z_NULL;
yading@10:     c->zstream.zfree = Z_NULL;
yading@10:     c->zstream.opaque = Z_NULL;
yading@10:     zret = inflateInit(&c->zstream);
yading@10:     if (zret != Z_OK) {
yading@10:         av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
yading@10:         return AVERROR_UNKNOWN;
yading@10:     }
yading@10: 
yading@10:     c->frame = av_frame_alloc();
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static av_cold int decode_end(AVCodecContext *avctx)
yading@10: {
yading@10:     CamtasiaContext * const c = avctx->priv_data;
yading@10: 
yading@10:     av_freep(&c->decomp_buf);
yading@10:     av_frame_free(&c->frame);
yading@10: 
yading@10:     inflateEnd(&c->zstream);
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: AVCodec ff_tscc_decoder = {
yading@10:     .name           = "camtasia",
yading@10:     .type           = AVMEDIA_TYPE_VIDEO,
yading@10:     .id             = AV_CODEC_ID_TSCC,
yading@10:     .priv_data_size = sizeof(CamtasiaContext),
yading@10:     .init           = decode_init,
yading@10:     .close          = decode_end,
yading@10:     .decode         = decode_frame,
yading@10:     .capabilities   = CODEC_CAP_DR1,
yading@10:     .long_name      = NULL_IF_CONFIG_SMALL("TechSmith Screen Capture Codec"),
yading@10: };