/* * 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#elsestatic 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;    }}#endifstatic 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,};