Subversion Repositories Kolibri OS

/*

 * 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 

#include 

#include "avcodec.h"

#include "internal.h"

#include "libavutil/common.h"

#if CONFIG_ZLIB

#include 

#endif

#include "libavutil/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, src_stride = FFALIGN(linelen, 4);

    uint8_t *dst = f->data[0];

    dst += (height - 1) * f->linesize[0];

    for (i = height; i; i--) {

        memcpy(dst, src, linelen);

        src += src_stride;

        dst -= f->linesize[0];

    }

}

static void add_frame_default(AVFrame *f, const uint8_t *src,

                              int linelen, int height) {

    int i, j, src_stride = FFALIGN(linelen, 4);

    uint8_t *dst = f->data[0];

    dst += (height - 1) * f->linesize[0];

    for (i = height; i; i--) {

        for (j = linelen; j; j--)

            *dst++ += *src++;

        src += src_stride - linelen;

        dst -= f->linesize[0] + linelen;

    }

}

static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,

                        AVPacket *avpkt) {

    const uint8_t *buf = avpkt->data;

    int buf_size = avpkt->size;

    CamStudioContext *c = avctx->priv_data;

    int ret;

    if (buf_size < 2) {

        av_log(avctx, AV_LOG_ERROR, "coded frame too small\n");

        return AVERROR_INVALIDDATA;

    }

    if ((ret = ff_reget_buffer(avctx, c->pic)) < 0)

        return ret;

    // decompress data

    switch ((buf[0] >> 1) & 7) {

        case 0: { // lzo compression

            int outlen = c->decomp_size, inlen = buf_size - 2;

            if (av_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

#if 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 AVERROR(ENOSYS);

#endif

        }

        default:

            av_log(avctx, AV_LOG_ERROR, "unknown compression\n");

            return AVERROR_INVALIDDATA;

    }

    // flip upside down, add difference frame

    if (buf[0] & 1) { // keyframe

        c->pic->pict_type = AV_PICTURE_TYPE_I;

        c->pic->key_frame = 1;

              copy_frame_default(c->pic, c->decomp_buf,

                                 c->linelen, c->height);

    } else {

        c->pic->pict_type = AV_PICTURE_TYPE_P;

        c->pic->key_frame = 0;

              add_frame_default(c->pic, c->decomp_buf,

                                c->linelen, c->height);

    }

    *got_frame = 1;

    if ((ret = av_frame_ref(data, c->pic)) < 0)

        return ret;

    return buf_size;

}

static av_cold int decode_init(AVCodecContext *avctx) {

    CamStudioContext *c = avctx->priv_data;

    int stride;

    switch (avctx->bits_per_coded_sample) {

        case 16: avctx->pix_fmt = AV_PIX_FMT_RGB555LE; break;

        case 24: avctx->pix_fmt = AV_PIX_FMT_BGR24; break;

        case 32: avctx->pix_fmt = AV_PIX_FMT_BGRA; break;

        default:

            av_log(avctx, AV_LOG_ERROR,

                   "CamStudio codec error: invalid depth %i bpp\n",

                   avctx->bits_per_coded_sample);

            return AVERROR_INVALIDDATA;

    }

    c->bpp = avctx->bits_per_coded_sample;

    c->linelen = avctx->width * avctx->bits_per_coded_sample / 8;

    c->height = avctx->height;

    stride = FFALIGN(c->linelen, 4);

    c->decomp_size = c->height * stride;

    c->decomp_buf = av_malloc(c->decomp_size + AV_LZO_OUTPUT_PADDING);

    if (!c->decomp_buf) {

        av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");

        return AVERROR(ENOMEM);

    }

    c->pic = av_frame_alloc();

    if (!c->pic)

        return AVERROR(ENOMEM);

    return 0;

}

static av_cold int decode_end(AVCodecContext *avctx) {

    CamStudioContext *c = avctx->priv_data;

    av_freep(&c->decomp_buf);

    av_frame_free(&c->pic);

    return 0;

}

AVCodec ff_cscd_decoder = {

    .name           = "camstudio",

    .long_name      = NULL_IF_CONFIG_SMALL("CamStudio"),

    .type           = AVMEDIA_TYPE_VIDEO,

    .id             = AV_CODEC_ID_CSCD,

    .priv_data_size = sizeof(CamStudioContext),

    .init           = decode_init,

    .close          = decode_end,

    .decode         = decode_frame,

    .capabilities   = CODEC_CAP_DR1,

};