1/*
2 * PNM image parser
3 * Copyright (c) 2002, 2003 Fabrice Bellard
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#include "parser.h" //for ParseContext
23#include "pnm.h"
24
25
26static int pnm_parse(AVCodecParserContext *s,
27                           AVCodecContext *avctx,
28                           const uint8_t **poutbuf, int *poutbuf_size,
29                           const uint8_t *buf, int buf_size)
30{
31    ParseContext *pc = s->priv_data;
32    PNMContext pnmctx;
33    int next;
34
35    for(; pc->overread>0; pc->overread--){
36        pc->buffer[pc->index++]= pc->buffer[pc->overread_index++];
37    }
38retry:
39    if(pc->index){
40        pnmctx.bytestream_start=
41        pnmctx.bytestream= pc->buffer;
42        pnmctx.bytestream_end= pc->buffer + pc->index;
43    }else{
44        pnmctx.bytestream_start=
45        pnmctx.bytestream= (uint8_t *) buf; /* casts avoid warnings */
46        pnmctx.bytestream_end= (uint8_t *) buf + buf_size;
47    }
48    if(ff_pnm_decode_header(avctx, &pnmctx) < 0){
49        if(pnmctx.bytestream < pnmctx.bytestream_end){
50            if(pc->index){
51                pc->index=0;
52            }else{
53                buf++;
54                buf_size--;
55            }
56            goto retry;
57        }
58#if 0
59        if(pc->index && pc->index*2 + FF_INPUT_BUFFER_PADDING_SIZE < pc->buffer_size && buf_size > pc->index){
60            memcpy(pc->buffer + pc->index, buf, pc->index);
61            pc->index += pc->index;
62            buf += pc->index;
63            buf_size -= pc->index;
64            goto retry;
65        }
66#endif
67        next= END_NOT_FOUND;
68    }else{
69        next= pnmctx.bytestream - pnmctx.bytestream_start
70            + avpicture_get_size(avctx->pix_fmt, avctx->width, avctx->height);
71        if(pnmctx.bytestream_start!=buf)
72            next-= pc->index;
73        if(next > buf_size)
74            next= END_NOT_FOUND;
75    }
76
77    if(ff_combine_frame(pc, next, &buf, &buf_size)<0){
78        *poutbuf = NULL;
79        *poutbuf_size = 0;
80        return buf_size;
81    }
82    *poutbuf = buf;
83    *poutbuf_size = buf_size;
84    return next;
85}
86
87AVCodecParser pnm_parser = {
88    { CODEC_ID_PGM, CODEC_ID_PGMYUV, CODEC_ID_PPM, CODEC_ID_PBM, CODEC_ID_PAM},
89    sizeof(ParseContext),
90    NULL,
91    pnm_parse,
92    ff_parse_close,
93};
94