/* * H.261 common code * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at> * Copyright (c) 2004 Maarten Daniels * * 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 */ /** * @file * H.261 codec */ #include "avcodec.h" #include "h261.h" #define IS_FIL(a) ((a) & MB_TYPE_H261_FIL) uint8_t ff_h261_rl_table_store[2][2 * MAX_RUN + MAX_LEVEL + 3]; static void h261_loop_filter(uint8_t *src, int stride) { int x, y, xy, yz; int temp[64]; for (x = 0; x < 8; x++) { temp[x] = 4 * src[x]; temp[x + 7 * 8] = 4 * src[x + 7 * stride]; } for (y = 1; y < 7; y++) { for (x = 0; x < 8; x++) { xy = y * stride + x; yz = y * 8 + x; temp[yz] = src[xy - stride] + 2 * src[xy] + src[xy + stride]; } } for (y = 0; y < 8; y++) { src[y * stride] = (temp[y * 8] + 2) >> 2; src[y * stride + 7] = (temp[y * 8 + 7] + 2) >> 2; for (x = 1; x < 7; x++) { xy = y * stride + x; yz = y * 8 + x; src[xy] = (temp[yz - 1] + 2 * temp[yz] + temp[yz + 1] + 8) >> 4; } } } void ff_h261_loop_filter(MpegEncContext *s) { H261Context *h = (H261Context *)s; const int linesize = s->linesize; const int uvlinesize = s->uvlinesize; uint8_t *dest_y = s->dest[0]; uint8_t *dest_cb = s->dest[1]; uint8_t *dest_cr = s->dest[2]; if (!(IS_FIL(h->mtype))) return; h261_loop_filter(dest_y, linesize); h261_loop_filter(dest_y + 8, linesize); h261_loop_filter(dest_y + 8 * linesize, linesize); h261_loop_filter(dest_y + 8 * linesize + 8, linesize); h261_loop_filter(dest_cb, uvlinesize); h261_loop_filter(dest_cr, uvlinesize); } av_cold void ff_h261_common_init(void) { static int done = 0; if (done) return; ff_rl_init(&ff_h261_rl_tcoeff, ff_h261_rl_table_store); done = 1; }