From 4bf4593c0d4cbc36d8fcaabe9e36b39134403c34 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tomas=20H=C3=A4rdin?= <g...@haerdin.se>
Date: Fri, 20 May 2022 11:44:06 +0200
Subject: [PATCH 2/8] libavcodec/jpeg2000_parser: Simplify, fix reset_context()
---
libavcodec/jpeg2000_parser.c | 23 ++++++++++-------------
1 file changed, 10 insertions(+), 13 deletions(-)
diff --git a/libavcodec/jpeg2000_parser.c b/libavcodec/jpeg2000_parser.c
index 9fac958dfa..a7f72710e4 100644
--- a/libavcodec/jpeg2000_parser.c
+++ b/libavcodec/jpeg2000_parser.c
@@ -51,7 +51,7 @@ static inline void reset_context(JPEG2000ParserContext *m)
ParseContext *pc = &m->pc;
pc->frame_start_found= 0;
- pc->state = 0;
+ pc->state64 = 0;
m->bytes_read = 0;
m->ft = 0;
m->skipped_codestream = 0;
@@ -82,16 +82,14 @@ static int find_frame_end(JPEG2000ParserContext *m, const uint8_t *buf, int buf_
{
ParseContext *pc= &m->pc;
int i;
- uint32_t state, next_state;
- uint64_t state64;
- state= pc->state;
- state64 = pc->state64;
+ uint32_t next_state;
+ uint64_t state64 = pc->state64;
+
if (buf_size == 0) {
return 0;
}
for (i = 0; i < buf_size; i++) {
- state = state << 8 | buf[i];
state64 = state64 << 8 | buf[i];
m->bytes_read++;
if (m->skip_bytes) {
@@ -132,9 +130,9 @@ static int find_frame_end(JPEG2000ParserContext *m, const uint8_t *buf, int buf_
}
m->fheader_read--;
}
- if (state == 0x0000000C && m->bytes_read >= 3) { // Indicates start of JP2 file. Check signature next.
+ if ((state64 & 0xFFFFFFFF) == 0x0000000C && m->bytes_read >= 3) { // Indicates start of JP2 file. Check signature next.
m->fheader_read = 8;
- } else if ((state & 0xFFFF) == 0xFF4F) {
+ } else if ((state64 & 0xFFFF) == 0xFF4F) {
m->in_codestream = 1;
if (!pc->frame_start_found) {
pc->frame_start_found = 1;
@@ -143,7 +141,7 @@ static int find_frame_end(JPEG2000ParserContext *m, const uint8_t *buf, int buf_
reset_context(m);
return i - 1;
}
- } else if ((state & 0xFFFF) == 0xFFD9) {
+ } 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) {
@@ -151,11 +149,11 @@ static int find_frame_end(JPEG2000ParserContext *m, const uint8_t *buf, int buf_
return i + 1; // End of frame detected, return frame size.
}
m->in_codestream = 0;
- } else if (m->in_codestream && (state & 0xFFFF) == 0xFF90) { // Are we in tile part header?
+ } else if (m->in_codestream && (state64 & 0xFFFF) == 0xFF90) { // Are we in tile part header?
m->read_tp = 8;
- } else if (pc->frame_start_found && info_marker((state & 0xFFFF0000)>>16) && m->in_codestream && (state & 0xFFFF)) {
+ } else if (pc->frame_start_found && info_marker((state64 & 0xFFFF0000)>>16) && m->in_codestream && (state64 & 0xFFFF)) {
// Calculate number of bytes to skip to get to end of the next marker.
- m->skip_bytes = (state & 0xFFFF)-1;
+ 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) {
@@ -168,7 +166,6 @@ static int find_frame_end(JPEG2000ParserContext *m, const uint8_t *buf, int buf_
}
}
- pc->state = state;
pc->state64 = state64;
return END_NOT_FOUND;
}
--
2.30.2
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