| 1 | /* |
| 2 | * DPX parser |
| 3 | * Copyright (c) 2013 Paul B Mahol |
| 4 | * |
| 5 | * This file is part of FFmpeg. |
| 6 | * |
| 7 | * FFmpeg is free software; you can redistribute it and/or |
| 8 | * modify it under the terms of the GNU Lesser General Public |
| 9 | * License as published by the Free Software Foundation; either |
| 10 | * version 2.1 of the License, or (at your option) any later version. |
| 11 | * |
| 12 | * FFmpeg is distributed in the hope that it will be useful, |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 15 | * Lesser General Public License for more details. |
| 16 | * |
| 17 | * You should have received a copy of the GNU Lesser General Public |
| 18 | * License along with FFmpeg; if not, write to the Free Software |
| 19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 20 | */ |
| 21 | |
| 22 | /** |
| 23 | * @file |
| 24 | * DPX parser |
| 25 | */ |
| 26 | |
| 27 | #include "libavutil/bswap.h" |
| 28 | #include "parser.h" |
| 29 | |
| 30 | typedef struct DPXParseContext { |
| 31 | ParseContext pc; |
| 32 | uint32_t index; |
| 33 | uint32_t fsize; |
| 34 | uint32_t remaining_size; |
| 35 | int is_be; |
| 36 | } DPXParseContext; |
| 37 | |
| 38 | static int dpx_parse(AVCodecParserContext *s, AVCodecContext *avctx, |
| 39 | const uint8_t **poutbuf, int *poutbuf_size, |
| 40 | const uint8_t *buf, int buf_size) |
| 41 | { |
| 42 | DPXParseContext *d = s->priv_data; |
| 43 | uint32_t state = d->pc.state; |
| 44 | int next = END_NOT_FOUND; |
| 45 | int i = 0; |
| 46 | |
| 47 | s->pict_type = AV_PICTURE_TYPE_I; |
| 48 | |
| 49 | *poutbuf_size = 0; |
| 50 | if (buf_size == 0) |
| 51 | next = 0; |
| 52 | |
| 53 | if (!d->pc.frame_start_found) { |
| 54 | for (; i < buf_size; i++) { |
| 55 | state = (state << 8) | buf[i]; |
| 56 | if (state == MKBETAG('S','D','P','X') || |
| 57 | state == MKTAG('S','D','P','X')) { |
| 58 | d->pc.frame_start_found = 1; |
| 59 | d->is_be = state == MKBETAG('S','D','P','X'); |
| 60 | d->index = 0; |
| 61 | break; |
| 62 | } |
| 63 | } |
| 64 | d->pc.state = state; |
| 65 | } else { |
| 66 | if (d->remaining_size) { |
| 67 | i = FFMIN(d->remaining_size, buf_size); |
| 68 | d->remaining_size -= i; |
| 69 | if (d->remaining_size) |
| 70 | goto flush; |
| 71 | } |
| 72 | } |
| 73 | |
| 74 | for (;d->pc.frame_start_found && i < buf_size; i++) { |
| 75 | d->pc.state = (d->pc.state << 8) | buf[i]; |
| 76 | d->index++; |
| 77 | if (d->index == 17) { |
| 78 | d->fsize = d->is_be ? d->pc.state : av_bswap32(d->pc.state); |
| 79 | if (d->fsize <= 1664) { |
| 80 | d->pc.frame_start_found = 0; |
| 81 | goto flush; |
| 82 | } |
| 83 | if (d->fsize > buf_size - i + 19) |
| 84 | d->remaining_size = d->fsize - buf_size + i - 19; |
| 85 | else |
| 86 | i += d->fsize - 19; |
| 87 | |
| 88 | break; |
| 89 | } else if (d->index > 17) { |
| 90 | if (d->pc.state == MKBETAG('S','D','P','X') || |
| 91 | d->pc.state == MKTAG('S','D','P','X')) { |
| 92 | next = i - 3; |
| 93 | break; |
| 94 | } |
| 95 | } |
| 96 | } |
| 97 | |
| 98 | flush: |
| 99 | if (ff_combine_frame(&d->pc, next, &buf, &buf_size) < 0) |
| 100 | return buf_size; |
| 101 | |
| 102 | d->pc.frame_start_found = 0; |
| 103 | |
| 104 | *poutbuf = buf; |
| 105 | *poutbuf_size = buf_size; |
| 106 | return next; |
| 107 | } |
| 108 | |
| 109 | AVCodecParser ff_dpx_parser = { |
| 110 | .codec_ids = { AV_CODEC_ID_DPX }, |
| 111 | .priv_data_size = sizeof(DPXParseContext), |
| 112 | .parser_parse = dpx_parse, |
| 113 | .parser_close = ff_parse_close, |
| 114 | }; |