| /* |
| * 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; |
| } |