/* * AVS2-P2/IEEE1857.4 video parser. * Copyright (c) 2018  Huiwen Ren <hwrenx@gmail.com> * * 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 */ #include "parser.h" #define SLICE_MAX_START_CODE    0x000001af #define ISPIC(x)  ((x) == 0xB3 || (x) == 0xB6)#define ISUNIT(x) ((x) == 0xB0 || (x) == 0xB1 || (x) == 0xB2 || ISPIC(x)) static int avs2_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size){    int pic_found  = pc->frame_start_found;    uint32_t state = pc->state;    int cur = 0;     if (!pic_found) {        for (; cur < buf_size; ++cur) {            state = (state<<8) | buf[cur];            if (ISUNIT(buf[cur])){                ++cur;                pic_found = 1;                break;            }        }    }     if (pic_found) {        if (!buf_size)            return END_NOT_FOUND;        for (; cur < buf_size; ++cur) {            state = (state << 8) | buf[cur];            if ((state & 0xFFFFFF00) == 0x100 && state > SLICE_MAX_START_CODE) {                pc->frame_start_found = 0;                pc->state = -1;                return cur - 3;            }        }    }     pc->frame_start_found = pic_found;    pc->state = state;     return END_NOT_FOUND;} static int avs2_parse(AVCodecParserContext *s, AVCodecContext *avctx,                      const uint8_t **poutbuf, int *poutbuf_size,                      const uint8_t *buf, int buf_size){    ParseContext *pc = s->priv_data;    int next;     if (s->flags & PARSER_FLAG_COMPLETE_FRAMES)  {        next = buf_size;    } else {        next = avs2_find_frame_end(pc, buf, buf_size);        if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) {            *poutbuf = NULL;            *poutbuf_size = 0;            return buf_size;        }    }     *poutbuf = buf;    *poutbuf_size = buf_size;     return next;} AVCodecParser ff_avs2_parser = {    .codec_ids      = { AV_CODEC_ID_AVS2 },    .priv_data_size = sizeof(ParseContext),    .parser_parse   = avs2_parse,    .parser_close   = ff_parse_close,    .split          = ff_mpeg4video_split,};