| 1 | /* |
| 2 | * CamStudio decoder |
| 3 | * Copyright (c) 2006 Reimar Doeffinger |
| 4 | * |
| 5 | * This file is part of FFmpeg. |
| 6 | * |
| 7 | * FFmpeg is free software; you can redistribute it and/or |
| 8 | * modify it under the terms of the GNU Lesser General Public |
| 9 | * 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 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 15 | * Lesser General Public License for more details. |
| 16 | * |
| 17 | * 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 | #include <stdio.h> |
| 22 | #include <stdlib.h> |
| 23 | |
| 24 | #include "avcodec.h" |
| 25 | #include "internal.h" |
| 26 | #include "libavutil/common.h" |
| 27 | |
| 28 | #if CONFIG_ZLIB |
| 29 | #include <zlib.h> |
| 30 | #endif |
| 31 | #include "libavutil/lzo.h" |
| 32 | |
| 33 | typedef struct { |
| 34 | AVFrame *pic; |
| 35 | int linelen, height, bpp; |
| 36 | unsigned int decomp_size; |
| 37 | unsigned char* decomp_buf; |
| 38 | } CamStudioContext; |
| 39 | |
| 40 | static void copy_frame_default(AVFrame *f, const uint8_t *src, |
| 41 | int linelen, int height) { |
| 42 | int i, src_stride = FFALIGN(linelen, 4); |
| 43 | uint8_t *dst = f->data[0]; |
| 44 | dst += (height - 1) * f->linesize[0]; |
| 45 | for (i = height; i; i--) { |
| 46 | memcpy(dst, src, linelen); |
| 47 | src += src_stride; |
| 48 | dst -= f->linesize[0]; |
| 49 | } |
| 50 | } |
| 51 | |
| 52 | static void add_frame_default(AVFrame *f, const uint8_t *src, |
| 53 | int linelen, int height) { |
| 54 | int i, j, src_stride = FFALIGN(linelen, 4); |
| 55 | uint8_t *dst = f->data[0]; |
| 56 | dst += (height - 1) * f->linesize[0]; |
| 57 | for (i = height; i; i--) { |
| 58 | for (j = linelen; j; j--) |
| 59 | *dst++ += *src++; |
| 60 | src += src_stride - linelen; |
| 61 | dst -= f->linesize[0] + linelen; |
| 62 | } |
| 63 | } |
| 64 | |
| 65 | static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, |
| 66 | AVPacket *avpkt) { |
| 67 | const uint8_t *buf = avpkt->data; |
| 68 | int buf_size = avpkt->size; |
| 69 | CamStudioContext *c = avctx->priv_data; |
| 70 | int ret; |
| 71 | |
| 72 | if (buf_size < 2) { |
| 73 | av_log(avctx, AV_LOG_ERROR, "coded frame too small\n"); |
| 74 | return AVERROR_INVALIDDATA; |
| 75 | } |
| 76 | |
| 77 | if ((ret = ff_reget_buffer(avctx, c->pic)) < 0) |
| 78 | return ret; |
| 79 | |
| 80 | // decompress data |
| 81 | switch ((buf[0] >> 1) & 7) { |
| 82 | case 0: { // lzo compression |
| 83 | int outlen = c->decomp_size, inlen = buf_size - 2; |
| 84 | if (av_lzo1x_decode(c->decomp_buf, &outlen, &buf[2], &inlen)) |
| 85 | av_log(avctx, AV_LOG_ERROR, "error during lzo decompression\n"); |
| 86 | break; |
| 87 | } |
| 88 | case 1: { // zlib compression |
| 89 | #if CONFIG_ZLIB |
| 90 | unsigned long dlen = c->decomp_size; |
| 91 | if (uncompress(c->decomp_buf, &dlen, &buf[2], buf_size - 2) != Z_OK) |
| 92 | av_log(avctx, AV_LOG_ERROR, "error during zlib decompression\n"); |
| 93 | break; |
| 94 | #else |
| 95 | av_log(avctx, AV_LOG_ERROR, "compiled without zlib support\n"); |
| 96 | return AVERROR(ENOSYS); |
| 97 | #endif |
| 98 | } |
| 99 | default: |
| 100 | av_log(avctx, AV_LOG_ERROR, "unknown compression\n"); |
| 101 | return AVERROR_INVALIDDATA; |
| 102 | } |
| 103 | |
| 104 | // flip upside down, add difference frame |
| 105 | if (buf[0] & 1) { // keyframe |
| 106 | c->pic->pict_type = AV_PICTURE_TYPE_I; |
| 107 | c->pic->key_frame = 1; |
| 108 | copy_frame_default(c->pic, c->decomp_buf, |
| 109 | c->linelen, c->height); |
| 110 | } else { |
| 111 | c->pic->pict_type = AV_PICTURE_TYPE_P; |
| 112 | c->pic->key_frame = 0; |
| 113 | add_frame_default(c->pic, c->decomp_buf, |
| 114 | c->linelen, c->height); |
| 115 | } |
| 116 | |
| 117 | *got_frame = 1; |
| 118 | if ((ret = av_frame_ref(data, c->pic)) < 0) |
| 119 | return ret; |
| 120 | |
| 121 | return buf_size; |
| 122 | } |
| 123 | |
| 124 | static av_cold int decode_init(AVCodecContext *avctx) { |
| 125 | CamStudioContext *c = avctx->priv_data; |
| 126 | int stride; |
| 127 | switch (avctx->bits_per_coded_sample) { |
| 128 | case 16: avctx->pix_fmt = AV_PIX_FMT_RGB555LE; break; |
| 129 | case 24: avctx->pix_fmt = AV_PIX_FMT_BGR24; break; |
| 130 | case 32: avctx->pix_fmt = AV_PIX_FMT_BGRA; break; |
| 131 | default: |
| 132 | av_log(avctx, AV_LOG_ERROR, |
| 133 | "CamStudio codec error: invalid depth %i bpp\n", |
| 134 | avctx->bits_per_coded_sample); |
| 135 | return AVERROR_INVALIDDATA; |
| 136 | } |
| 137 | c->bpp = avctx->bits_per_coded_sample; |
| 138 | c->linelen = avctx->width * avctx->bits_per_coded_sample / 8; |
| 139 | c->height = avctx->height; |
| 140 | stride = FFALIGN(c->linelen, 4); |
| 141 | c->decomp_size = c->height * stride; |
| 142 | c->decomp_buf = av_malloc(c->decomp_size + AV_LZO_OUTPUT_PADDING); |
| 143 | if (!c->decomp_buf) { |
| 144 | av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n"); |
| 145 | return AVERROR(ENOMEM); |
| 146 | } |
| 147 | c->pic = av_frame_alloc(); |
| 148 | if (!c->pic) |
| 149 | return AVERROR(ENOMEM); |
| 150 | return 0; |
| 151 | } |
| 152 | |
| 153 | static av_cold int decode_end(AVCodecContext *avctx) { |
| 154 | CamStudioContext *c = avctx->priv_data; |
| 155 | av_freep(&c->decomp_buf); |
| 156 | av_frame_free(&c->pic); |
| 157 | return 0; |
| 158 | } |
| 159 | |
| 160 | AVCodec ff_cscd_decoder = { |
| 161 | .name = "camstudio", |
| 162 | .long_name = NULL_IF_CONFIG_SMALL("CamStudio"), |
| 163 | .type = AVMEDIA_TYPE_VIDEO, |
| 164 | .id = AV_CODEC_ID_CSCD, |
| 165 | .priv_data_size = sizeof(CamStudioContext), |
| 166 | .init = decode_init, |
| 167 | .close = decode_end, |
| 168 | .decode = decode_frame, |
| 169 | .capabilities = CODEC_CAP_DR1, |
| 170 | }; |