/* * AVS video decoder. * Copyright (c) 2006 Aurelien Jacobs <aurel@gnuage.org> * * This library 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 of the License, or (at your option) any later version. * * This library 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 this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ #include "avcodec.h" #include "bitstream.h" typedef struct { AVFrame picture; } avs_context_t; typedef enum { AVS_VIDEO = 0x01, AVS_AUDIO = 0x02, AVS_PALETTE = 0x03, AVS_GAME_DATA = 0x04, } avs_block_type_t; typedef enum { AVS_I_FRAME = 0x00, AVS_P_FRAME_3X3 = 0x01, AVS_P_FRAME_2X2 = 0x02, AVS_P_FRAME_2X3 = 0x03, } avs_video_sub_type_t; static int avs_decode_frame(AVCodecContext * avctx, void *data, int *data_size, uint8_t * buf, int buf_size) { avs_context_t *const avs = avctx->priv_data; AVFrame *picture = data; AVFrame *const p = (AVFrame *) & avs->picture; uint8_t *table, *vect, *out; int i, j, x, y, stride, vect_w = 3, vect_h = 3; int sub_type; avs_block_type_t type; GetBitContext change_map; if (avctx->reget_buffer(avctx, p)) { av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n"); return -1; } p->reference = 1; p->pict_type = FF_P_TYPE; p->key_frame = 0; out = avs->picture.data[0]; stride = avs->picture.linesize[0]; sub_type = buf[0]; type = buf[1]; buf += 4; if (type == AVS_PALETTE) { int first, last; uint32_t *pal = (uint32_t *) avs->picture.data[1]; first = LE_16(buf); last = first + LE_16(buf + 2); buf += 4; for (i=first; i<last; i++, buf+=3) pal[i] = (buf[0] << 18) | (buf[1] << 10) | (buf[2] << 2); sub_type = buf[0]; type = buf[1]; buf += 4; } if (type != AVS_VIDEO) return -1; switch (sub_type) { case AVS_I_FRAME: p->pict_type = FF_I_TYPE; p->key_frame = 1; case AVS_P_FRAME_3X3: vect_w = 3; vect_h = 3; break; case AVS_P_FRAME_2X2: vect_w = 2; vect_h = 2; break; case AVS_P_FRAME_2X3: vect_w = 2; vect_h = 3; break; default: return -1; } table = buf + (256 * vect_w * vect_h); if (sub_type != AVS_I_FRAME) { int map_size = ((318 / vect_w + 7) / 8) * (198 / vect_h); init_get_bits(&change_map, table, map_size); table += map_size; } for (y=0; y<198; y+=vect_h) { for (x=0; x<318; x+=vect_w) { if (sub_type == AVS_I_FRAME || get_bits1(&change_map)) { vect = &buf[*table++ * (vect_w * vect_h)]; for (j=0; j<vect_w; j++) { out[(y + 0) * stride + x + j] = vect[(0 * vect_w) + j]; out[(y + 1) * stride + x + j] = vect[(1 * vect_w) + j]; if (vect_h == 3) out[(y + 2) * stride + x + j] = vect[(2 * vect_w) + j]; } } } if (sub_type != AVS_I_FRAME) align_get_bits(&change_map); } *picture = *(AVFrame *) & avs->picture; *data_size = sizeof(AVPicture); return buf_size; } static int avs_decode_init(AVCodecContext * avctx) { avctx->pix_fmt = PIX_FMT_PAL8; return 0; } AVCodec avs_decoder = { "avs", CODEC_TYPE_VIDEO, CODEC_ID_AVS, sizeof(avs_context_t), avs_decode_init, NULL, NULL, avs_decode_frame, CODEC_CAP_DR1, };