3 * Copyright (c) 2002, 2003 Fabrice Bellard
5 * This file is part of FFmpeg.
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.
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.
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
22 #include "libavutil/avassert.h"
23 #include "libavutil/imgutils.h"
25 #include "parser.h" //for ParseContext
28 typedef struct PNMParseContext {
34 static int pnm_parse(AVCodecParserContext *s, AVCodecContext *avctx,
35 const uint8_t **poutbuf, int *poutbuf_size,
36 const uint8_t *buf, int buf_size)
38 PNMParseContext *pnmpc = s->priv_data;
39 ParseContext *pc = &pnmpc->pc;
41 int next = END_NOT_FOUND;
44 for (; pc->overread > 0; pc->overread--) {
45 pc->buffer[pc->index++]= pc->buffer[pc->overread_index++];
48 if (pnmpc->remaining_bytes) {
49 int inc = FFMIN(pnmpc->remaining_bytes, buf_size);
51 pnmpc->remaining_bytes -= inc;
53 if (!pnmpc->remaining_bytes)
60 pnmctx.bytestream_start =
61 pnmctx.bytestream = pc->buffer;
62 pnmctx.bytestream_end = pc->buffer + pc->index;
64 pnmctx.bytestream_start =
65 pnmctx.bytestream = (uint8_t *) buf + skip; /* casts avoid warnings */
66 pnmctx.bytestream_end = (uint8_t *) buf + buf_size - skip;
68 if (ff_pnm_decode_header(avctx, &pnmctx) < 0) {
69 if (pnmctx.bytestream < pnmctx.bytestream_end) {
73 unsigned step = FFMAX(1, pnmctx.bytestream - pnmctx.bytestream_start);
79 } else if (pnmctx.type < 4) {
80 uint8_t *bs = pnmctx.bytestream;
81 const uint8_t *end = pnmctx.bytestream_end;
85 av_assert0(pnmpc->ascii_scan <= end - bs);
86 bs += pnmpc->ascii_scan;
94 while (c != '\n' && bs < end)
96 } else if (c == 'P') {
97 next = bs - pnmctx.bytestream_start + skip - 1;
98 pnmpc->ascii_scan = 0;
102 if (next == END_NOT_FOUND)
103 pnmpc->ascii_scan = sync - pnmctx.bytestream + skip;
105 next = pnmctx.bytestream - pnmctx.bytestream_start + skip
106 + av_image_get_buffer_size(avctx->pix_fmt, avctx->width, avctx->height, 1);
108 if (next != END_NOT_FOUND && pnmctx.bytestream_start != buf + skip)
110 if (next > buf_size) {
111 pnmpc->remaining_bytes = next - buf_size;
112 next = END_NOT_FOUND;
115 if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
121 *poutbuf_size = buf_size;
125 AVCodecParser ff_pnm_parser = {
126 .codec_ids = { AV_CODEC_ID_PGM, AV_CODEC_ID_PGMYUV, AV_CODEC_ID_PPM,
127 AV_CODEC_ID_PBM, AV_CODEC_ID_PAM },
128 .priv_data_size = sizeof(PNMParseContext),
129 .parser_parse = pnm_parse,
130 .parser_close = ff_parse_close,