mirror of
https://github.com/FFmpeg/FFmpeg.git
synced 2026-11-06 05:17:42 +00:00
Rainbaby
8aff7f9f87
The Broadcasting profile codes its macroblock layer with the arithmetic coder of clause 8.4. This is the decoder only; its renormalization loops end with the buffer, so truncated input terminates. Signed-off-by: Rainbaby <r@bgr.jp>
55 lines
1.7 KiB
C
55 lines
1.7 KiB
C
/*
|
|
* Chinese AVS video (AVS1-P16, Broadcasting profile) AEC decoder.
|
|
* Copyright (c) 2026 Rainbaby <r@bgr.jp>
|
|
*
|
|
* 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
|
|
* Chinese AVS video (AVS1-P16, Broadcasting profile) AEC decoder
|
|
*
|
|
* Clause numbers refer to GY/T 257.1-2012. The renormalization loops end
|
|
* with the buffer, so truncated input terminates. The caller must have
|
|
* removed the annex A pseudo start codes from the payload.
|
|
*/
|
|
|
|
#include <stdint.h>
|
|
|
|
#include "cavs_aec.h"
|
|
#include "get_bits.h"
|
|
|
|
void ff_cavs_aec_init(CAVSAECContext *aec, GetBitContext *gb)
|
|
{
|
|
for (int i = 0; i < CAVS_AEC_NUM_CTX; i++) {
|
|
aec->ctx[i].mps = 0;
|
|
aec->ctx[i].cycno = 0;
|
|
aec->ctx[i].lg_pmps = CAVS_AEC_LGPMPS_INIT;
|
|
}
|
|
|
|
aec->gb = gb;
|
|
aec->rs1 = 0;
|
|
aec->rt1 = CAVS_AEC_RT1_INIT;
|
|
aec->vs = 0;
|
|
aec->vt = get_bits(gb, 9);
|
|
while (!((aec->vt >> 8) & 0x01) && get_bits_left(gb) > 0) {
|
|
aec->vt = (aec->vt << 1) | get_bits1(gb);
|
|
aec->vs++;
|
|
}
|
|
aec->vt &= 0xFF;
|
|
}
|