On 07/08/2016 04:08 AM, Jayathirth D V wrote:
Hi,
In JDK-8152672 <https://bugs.openjdk.java.net/browse/JDK-8152672> we
modified skipImage() in JpegImageReader.java and added tighter checks
for parsing Jpeg data.
We have to find any marker,0 or EOF after we find "FF" while parsing
JPEG data.
But in JDK-8160943 <https://bugs.openjdk.java.net/browse/JDK-8160943>
we have gap between APP0 marker and DQT(FF DB) marker which contains
data "00 FF".
APP0_End -> 00 FF -> FF DB(DQT)
So after we skip APP0 marker we find two bytes of data which is "FF
FF". In the present code we consider this as invalid marker.
See https://www.w3.org/Graphics/JPEG/itu-t81.pdf
B.1.1.2 Markers
Markers serve to identify the various structural parts of the compressed
data formats.
Most markers start marker segments containing a related group of parameters;
some markers stand alone. All markers are assigned two-byte codes: an
X'FF' byte followed by a byte which is not equal to 0 or X'FF' (see
Table B.1).
Any marker may optionally be preceded by any number of fill bytes,
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
which are bytes assigned code X'FF
^^^^^^^^^^^^^^^^^^^^^^
-phil.
Because of this JDK-8160943
<https://bugs.openjdk.java.net/browse/JDK-8160943> is failing.
Is the length of APP0 marker not valid in the image or we should not
consider "FF FF" as invalid maker?
Please let me know your input.
Thanks,
Jay
