mirror of
https://github.com/nyanmisaka/ffmpeg-rockchip.git
synced 2025-10-31 20:42:49 +08:00
220 lines
7.5 KiB
C
220 lines
7.5 KiB
C
/*
|
|
* JPEG2000 parser
|
|
* Copyright (c) 2020 Gautam Ramakrishnan
|
|
*
|
|
* 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
|
|
*/
|
|
|
|
/**
|
|
* @file
|
|
* JPEG2000 parser.
|
|
*/
|
|
|
|
#include "parser.h"
|
|
|
|
/* Whether frame is jp2 file or codestream
|
|
*/
|
|
enum frame_type {
|
|
jp2_file = 1,
|
|
j2k_cstream
|
|
};
|
|
|
|
typedef struct JPEG2000ParserContext {
|
|
ParseContext pc;
|
|
uint64_t bytes_read;
|
|
uint64_t fheader_state;
|
|
uint32_t skip_bytes; // skip bytes inside codestream data
|
|
enum frame_type ft; // 1 if file, 2 if codestream
|
|
uint8_t fheader_read; // are we reading
|
|
uint8_t reading_file_header;
|
|
uint8_t skipped_codestream;
|
|
uint8_t read_tp;
|
|
uint8_t in_codestream;
|
|
} JPEG2000ParserContext;
|
|
|
|
static inline void reset_context(JPEG2000ParserContext *m)
|
|
{
|
|
ParseContext *pc = &m->pc;
|
|
|
|
pc->frame_start_found= 0;
|
|
pc->state64 = 0;
|
|
m->bytes_read = 0;
|
|
m->ft = 0;
|
|
m->skipped_codestream = 0;
|
|
m->fheader_read = 0;
|
|
m->skip_bytes = 0;
|
|
m->read_tp = 0;
|
|
m->in_codestream = 0;
|
|
}
|
|
|
|
/* Returns 1 if marker has any data which can be skipped
|
|
*/
|
|
static uint8_t info_marker(uint16_t marker)
|
|
{
|
|
static const uint8_t lut[256] = {
|
|
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
|
|
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
|
|
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
|
|
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
|
|
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, // 0xFF4F
|
|
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
|
|
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
|
|
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
|
|
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
|
|
0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 0xFF90 0xFF92 0xFF93
|
|
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
|
|
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
|
|
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
|
|
1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, // 0xFFD9
|
|
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
|
|
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
|
|
};
|
|
return marker < 0xFF00 ? 0 : lut[marker & 0xFF];
|
|
}
|
|
|
|
/**
|
|
* Find the end of the current frame in the bitstream.
|
|
* @return the position of the first byte of the next frame, or -1
|
|
*/
|
|
static int find_frame_end(JPEG2000ParserContext *m, const uint8_t *buf, int buf_size)
|
|
{
|
|
ParseContext *pc= &m->pc;
|
|
int i;
|
|
uint64_t state64 = pc->state64;
|
|
uint64_t bytes_read = m->bytes_read;
|
|
|
|
if (buf_size == 0) {
|
|
return 0;
|
|
}
|
|
|
|
for (i = 0; i < buf_size; i++) {
|
|
state64 = state64 << 8 | buf[i];
|
|
bytes_read++;
|
|
if (m->skip_bytes) {
|
|
// handle long skips
|
|
if (m->skip_bytes > 8) {
|
|
// need -9 else buf_size - i == 8 ==> i == buf_size after this,
|
|
// and thus i == buf_size + 1 after the loop
|
|
int skip = FFMIN(FFMIN((int64_t)m->skip_bytes - 8, buf_size - i - 9), INT_MAX);
|
|
if (skip > 0) {
|
|
m->skip_bytes -= skip;
|
|
i += skip;
|
|
bytes_read += skip;
|
|
}
|
|
}
|
|
m->skip_bytes--;
|
|
continue;
|
|
}
|
|
if (m->read_tp) { // Find out how many bytes inside Tile part codestream to skip.
|
|
if (m->read_tp == 1) {
|
|
m->skip_bytes = (state64 & 0xFFFFFFFF) - 9 > 0?
|
|
(state64 & 0xFFFFFFFF) - 9 : 0;
|
|
}
|
|
m->read_tp--;
|
|
continue;
|
|
}
|
|
if (m->fheader_read) {
|
|
if (m->fheader_read == 1) {
|
|
if (state64 == 0x6A5020200D0A870A) { // JP2 signature box value.
|
|
if (pc->frame_start_found) {
|
|
pc->frame_start_found = 0;
|
|
reset_context(m);
|
|
return i - 11;
|
|
} else {
|
|
pc->frame_start_found = 1;
|
|
m->ft = jp2_file;
|
|
}
|
|
}
|
|
}
|
|
m->fheader_read--;
|
|
}
|
|
if ((state64 & 0xFFFFFFFF) == 0x0000000C && bytes_read >= 3) { // Indicates start of JP2 file. Check signature next.
|
|
m->fheader_read = 8;
|
|
} else if ((state64 & 0xFFFF) == 0xFF4F) {
|
|
m->in_codestream = 1;
|
|
if (!pc->frame_start_found) {
|
|
pc->frame_start_found = 1;
|
|
m->ft = j2k_cstream;
|
|
} else if (pc->frame_start_found && m->ft == jp2_file && m->skipped_codestream) {
|
|
reset_context(m);
|
|
return i - 1;
|
|
}
|
|
} else if ((state64 & 0xFFFF) == 0xFFD9) {
|
|
if (pc->frame_start_found && m->ft == jp2_file) {
|
|
m->skipped_codestream = 1;
|
|
} else if (pc->frame_start_found && m->ft == j2k_cstream) {
|
|
reset_context(m);
|
|
return i + 1; // End of frame detected, return frame size.
|
|
}
|
|
m->in_codestream = 0;
|
|
} else if (m->in_codestream) {
|
|
if ((state64 & 0xFFFF) == 0xFF90) { // Are we in tile part header?
|
|
m->read_tp = 8;
|
|
} else if (info_marker((state64 & 0xFFFF0000)>>16) && pc->frame_start_found && (state64 & 0xFFFF)) {
|
|
// Calculate number of bytes to skip to get to end of the next marker.
|
|
m->skip_bytes = (state64 & 0xFFFF)-1;
|
|
|
|
// If the next marker is an info marker, skip to the end of of the marker length.
|
|
if (i + m->skip_bytes + 1 < buf_size) {
|
|
uint32_t next_state = (buf[i + m->skip_bytes] << 8) | buf[i + m->skip_bytes + 1];
|
|
if (info_marker(next_state)) {
|
|
// Skip an additional 2 bytes to get to the end of the marker length.
|
|
m->skip_bytes += 2;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
pc->state64 = state64;
|
|
m->bytes_read = bytes_read;
|
|
return END_NOT_FOUND;
|
|
}
|
|
|
|
static int jpeg2000_parse(AVCodecParserContext *s,
|
|
AVCodecContext *avctx,
|
|
const uint8_t **poutbuf, int *poutbuf_size,
|
|
const uint8_t *buf, int buf_size)
|
|
{
|
|
JPEG2000ParserContext *m = s->priv_data;
|
|
ParseContext *pc = &m->pc;
|
|
int next;
|
|
|
|
if(s->flags & PARSER_FLAG_COMPLETE_FRAMES) {
|
|
next= buf_size;
|
|
} else {
|
|
next= find_frame_end(m, 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;
|
|
}
|
|
|
|
const AVCodecParser ff_jpeg2000_parser = {
|
|
.codec_ids = { AV_CODEC_ID_JPEG2000 },
|
|
.priv_data_size = sizeof(JPEG2000ParserContext),
|
|
.parser_parse = jpeg2000_parse,
|
|
.parser_close = ff_parse_close,
|
|
};
|