From 87bd298abeb901fe16383a0d267502cc7fc03878 Mon Sep 17 00:00:00 2001 From: Paul B Mahol Date: Mon, 1 Dec 2014 16:20:09 +0100 Subject: DPX parser Additional improvements and fixes by Michael Niedermayer . Signed-off-by: Vittorio Giovara --- libavcodec/dpx_parser.c | 116 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 116 insertions(+) create mode 100644 libavcodec/dpx_parser.c (limited to 'libavcodec/dpx_parser.c') diff --git a/libavcodec/dpx_parser.c b/libavcodec/dpx_parser.c new file mode 100644 index 0000000000..e3a7ac5c35 --- /dev/null +++ b/libavcodec/dpx_parser.c @@ -0,0 +1,116 @@ +/* + * DPX parser + * Copyright (c) 2013 Paul B Mahol + * + * This file is part of Libav. + * + * Libav 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. + * + * Libav 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 Libav; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +/** + * @file + * DPX parser + */ + +#include "libavutil/bswap.h" +#include "libavutil/common.h" + +#include "parser.h" + +typedef struct DPXParseContext { + ParseContext pc; + uint32_t index; + uint32_t fsize; + uint32_t remaining_size; + int is_be; +} DPXParseContext; + +static int dpx_parse(AVCodecParserContext *s, AVCodecContext *avctx, + const uint8_t **poutbuf, int *poutbuf_size, + const uint8_t *buf, int buf_size) +{ + DPXParseContext *d = s->priv_data; + uint32_t state = d->pc.state; + int next = END_NOT_FOUND; + int i = 0; + + s->pict_type = AV_PICTURE_TYPE_I; + + *poutbuf_size = 0; + if (buf_size == 0) + next = 0; + + if (!d->pc.frame_start_found) { + for (; i < buf_size; i++) { + state = (state << 8) | buf[i]; + if (state == MKBETAG('S','D','P','X') || + state == MKTAG('S','D','P','X')) { + d->pc.frame_start_found = 1; + d->is_be = state == MKBETAG('S','D','P','X'); + d->index = 0; + break; + } + } + d->pc.state = state; + } else { + if (d->remaining_size) { + i = FFMIN(d->remaining_size, buf_size); + d->remaining_size -= i; + if (d->remaining_size) + goto flush; + } + } + + for (; d->pc.frame_start_found && i < buf_size; i++) { + d->pc.state = (d->pc.state << 8) | buf[i]; + d->index++; + if (d->index == 17) { + d->fsize = d->is_be ? d->pc.state : av_bswap32(d->pc.state); + if (d->fsize <= 1664) { + d->pc.frame_start_found = 0; + goto flush; + } + if (d->fsize > buf_size - i + 19) + d->remaining_size = d->fsize - buf_size + i - 19; + else + i += d->fsize - 19; + + break; + } else if (d->index > 17) { + if (d->pc.state == MKBETAG('S','D','P','X') || + d->pc.state == MKTAG('S','D','P','X')) { + next = i - 3; + break; + } + } + } + +flush: + if (ff_combine_frame(&d->pc, next, &buf, &buf_size) < 0) + return buf_size; + + d->pc.frame_start_found = 0; + + *poutbuf = buf; + *poutbuf_size = buf_size; + return next; +} + +AVCodecParser ff_dpx_parser = { + .codec_ids = { AV_CODEC_ID_DPX }, + .priv_data_size = sizeof(DPXParseContext), + .parser_parse = dpx_parse, + .parser_close = ff_parse_close, +}; -- cgit v1.2.3