cscd.c 8.28 KB
Newer Older
1 2 3 4
/*
 * CamStudio decoder
 * Copyright (c) 2006 Reimar Doeffinger
 *
5 6 7
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
8 9
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
10
 * version 2.1 of the License, or (at your option) any later version.
11
 *
12
 * FFmpeg is distributed in the hope that it will be useful,
13 14 15 16 17
 * 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
18
 * License along with FFmpeg; if not, write to the Free Software
19
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 21 22 23 24 25
 */
#include <stdio.h>
#include <stdlib.h>

#include "avcodec.h"

26
#if CONFIG_ZLIB
27 28
#include <zlib.h>
#endif
29
#include "libavutil/lzo.h"
30 31 32 33 34 35 36 37

typedef struct {
    AVFrame pic;
    int linelen, height, bpp;
    unsigned int decomp_size;
    unsigned char* decomp_buf;
} CamStudioContext;

38
static void copy_frame_default(AVFrame *f, const uint8_t *src, int src_stride,
39 40 41 42 43 44
                               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);
45
        src += src_stride;
46 47 48 49
        dst -= f->linesize[0];
    }
}

50
static void add_frame_default(AVFrame *f, const uint8_t *src, int src_stride,
51 52 53 54 55 56 57
                              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++;
58
        src += src_stride - linelen;
59 60 61 62
        dst -= f->linesize[0] + linelen;
    }
}

63
#if !HAVE_BIGENDIAN
64 65 66 67
#define copy_frame_16(f, s, l, h) copy_frame_default(f, s, l, l, h)
#define copy_frame_32(f, s, l, h) copy_frame_default(f, s, l, l, h)
#define add_frame_16(f, s, l, h) add_frame_default(f, s, l, l, h)
#define add_frame_32(f, s, l, h) add_frame_default(f, s, l, l, h)
68
#else
69
static void copy_frame_16(AVFrame *f, const uint8_t *src,
70 71 72 73 74 75 76 77 78 79 80 81 82 83 84
                          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;
    }
}

85
static void copy_frame_32(AVFrame *f, const uint8_t *src,
86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102
                          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;
    }
}

103
static void add_frame_16(AVFrame *f, const uint8_t *src,
104 105 106 107 108 109 110 111 112 113 114 115 116 117 118
                         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;
    }
}

119
static void add_frame_32(AVFrame *f, const uint8_t *src,
120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138
                         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;
    }
}
#endif

static int decode_frame(AVCodecContext *avctx, void *data, int *data_size,
139 140 141
                        AVPacket *avpkt) {
    const uint8_t *buf = avpkt->data;
    int buf_size = avpkt->size;
142
    CamStudioContext *c = avctx->priv_data;
143 144 145 146 147 148 149 150 151
    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);
152
    c->pic.reference = 3;
153 154 155 156 157 158 159 160 161 162
    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
163
            int outlen = c->decomp_size, inlen = buf_size - 2;
164
            if (av_lzo1x_decode(c->decomp_buf, &outlen, &buf[2], &inlen))
165 166 167 168
                av_log(avctx, AV_LOG_ERROR, "error during lzo decompression\n");
            break;
        }
        case 1: { // zlib compression
169
#if CONFIG_ZLIB
170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185
            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
186
        c->pic.pict_type = AV_PICTURE_TYPE_I;
187 188 189 190 191 192 193 194 195
        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:
196 197
              copy_frame_default(&c->pic, c->decomp_buf, FFALIGN(c->linelen, 4),
                                 c->linelen, c->height);
198 199
        }
    } else {
200
        c->pic.pict_type = AV_PICTURE_TYPE_P;
201 202 203 204 205 206 207 208 209
        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:
210 211
              add_frame_default(&c->pic, c->decomp_buf, FFALIGN(c->linelen, 4),
                                c->linelen, c->height);
212 213 214 215 216 217 218 219
        }
    }

    *picture = c->pic;
    *data_size = sizeof(AVFrame);
    return buf_size;
}

220
static av_cold int decode_init(AVCodecContext *avctx) {
221
    CamStudioContext *c = avctx->priv_data;
222
    int stride;
223
    switch (avctx->bits_per_coded_sample) {
224
        case 16: avctx->pix_fmt = PIX_FMT_RGB555; break;
225
        case 24: avctx->pix_fmt = PIX_FMT_BGR24; break;
226
        case 32: avctx->pix_fmt = PIX_FMT_RGB32; break;
227 228
        default:
            av_log(avctx, AV_LOG_ERROR,
229
                   "CamStudio codec error: invalid depth %i bpp\n",
230
                   avctx->bits_per_coded_sample);
Reimar Döffinger's avatar
Reimar Döffinger committed
231
            return 1;
232
    }
233
    c->bpp = avctx->bits_per_coded_sample;
234
    avcodec_get_frame_defaults(&c->pic);
235
    c->pic.data[0] = NULL;
236
    c->linelen = avctx->width * avctx->bits_per_coded_sample / 8;
237
    c->height = avctx->height;
238 239 240 241
    stride = c->linelen;
    if (avctx->bits_per_coded_sample == 24)
        stride = FFALIGN(stride, 4);
    c->decomp_size = c->height * stride;
242
    c->decomp_buf = av_malloc(c->decomp_size + AV_LZO_OUTPUT_PADDING);
243 244 245 246 247 248 249
    if (!c->decomp_buf) {
        av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
        return 1;
    }
    return 0;
}

250
static av_cold int decode_end(AVCodecContext *avctx) {
251
    CamStudioContext *c = avctx->priv_data;
252 253 254 255 256 257
    av_freep(&c->decomp_buf);
    if (c->pic.data[0])
        avctx->release_buffer(avctx, &c->pic);
    return 0;
}

258
AVCodec ff_cscd_decoder = {
259 260 261 262 263 264 265 266
    .name           = "camstudio",
    .type           = AVMEDIA_TYPE_VIDEO,
    .id             = CODEC_ID_CSCD,
    .priv_data_size = sizeof(CamStudioContext),
    .init           = decode_init,
    .close          = decode_end,
    .decode         = decode_frame,
    .capabilities   = CODEC_CAP_DR1,
267
    .long_name = NULL_IF_CONFIG_SMALL("CamStudio"),
268 269
};