/* * LCL (LossLess Codec Library) Codec * Copyright (c) 2002-2004 Roberto Togni * * This file is part of Libav. * * Libav 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. * * Libav 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 Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** * @file * LCL (LossLess Codec Library) Video Codec * Decoder for MSZH and ZLIB codecs * Experimental encoder for ZLIB RGB24 * * Fourcc: MSZH, ZLIB * * Original Win32 dll: * Ver2.23 By Kenji Oshima 2000.09.20 * avimszh.dll, avizlib.dll * * A description of the decoding algorithm can be found here: * http://www.pcisys.net/~melanson/codecs * * Supports: BGR24 (RGB 24bpp) * */ #include <stdio.h> #include <stdlib.h> #include "avcodec.h" #include "lcl.h" #include <zlib.h> /* * Decoder context */ typedef struct LclEncContext { AVCodecContext *avctx; AVFrame pic; // Image type int imgtype; // Compression type int compression; // Flags int flags; z_stream zstream; } LclEncContext; /* * * Encode a frame * */ static int encode_frame(AVCodecContext *avctx, unsigned char *buf, int buf_size, void *data){ LclEncContext *c = avctx->priv_data; AVFrame *pict = data; AVFrame * const p = &c->pic; int i; int zret; // Zlib return code *p = *pict; p->pict_type= AV_PICTURE_TYPE_I; p->key_frame= 1; if(avctx->pix_fmt != PIX_FMT_BGR24){ av_log(avctx, AV_LOG_ERROR, "Format not supported!\n"); return -1; } zret = deflateReset(&c->zstream); if (zret != Z_OK) { av_log(avctx, AV_LOG_ERROR, "Deflate reset error: %d\n", zret); return -1; } c->zstream.next_out = buf; c->zstream.avail_out = buf_size; for(i = avctx->height - 1; i >= 0; i--) { c->zstream.next_in = p->data[0]+p->linesize[0]*i; c->zstream.avail_in = avctx->width*3; zret = deflate(&c->zstream, Z_NO_FLUSH); if (zret != Z_OK) { av_log(avctx, AV_LOG_ERROR, "Deflate error: %d\n", zret); return -1; } } zret = deflate(&c->zstream, Z_FINISH); if (zret != Z_STREAM_END) { av_log(avctx, AV_LOG_ERROR, "Deflate error: %d\n", zret); return -1; } return c->zstream.total_out; } /* * * Init lcl encoder * */ static av_cold int encode_init(AVCodecContext *avctx) { LclEncContext *c = avctx->priv_data; int zret; // Zlib return code c->avctx= avctx; assert(avctx->width && avctx->height); avctx->extradata= av_mallocz(8); avctx->coded_frame= &c->pic; // Will be user settable someday c->compression = 6; c->flags = 0; c->imgtype = IMGTYPE_RGB24; avctx->bits_per_coded_sample= 24; avctx->extradata[0]= 4; avctx->extradata[1]= 0; avctx->extradata[2]= 0; avctx->extradata[3]= 0; avctx->extradata[4]= c->imgtype; avctx->extradata[5]= c->compression; avctx->extradata[6]= c->flags; avctx->extradata[7]= CODEC_ZLIB; c->avctx->extradata_size= 8; c->zstream.zalloc = Z_NULL; c->zstream.zfree = Z_NULL; c->zstream.opaque = Z_NULL; zret = deflateInit(&c->zstream, c->compression); if (zret != Z_OK) { av_log(avctx, AV_LOG_ERROR, "Deflate init error: %d\n", zret); return 1; } return 0; } /* * * Uninit lcl encoder * */ static av_cold int encode_end(AVCodecContext *avctx) { LclEncContext *c = avctx->priv_data; av_freep(&avctx->extradata); deflateEnd(&c->zstream); return 0; } AVCodec ff_zlib_encoder = { "zlib", AVMEDIA_TYPE_VIDEO, CODEC_ID_ZLIB, sizeof(LclEncContext), encode_init, encode_frame, encode_end, .pix_fmts = (const enum PixelFormat[]) { PIX_FMT_BGR24, PIX_FMT_NONE }, .long_name = NULL_IF_CONFIG_SMALL("LCL (LossLess Codec Library) ZLIB"), };