Re: [OpenJDK 2D-Dev] Review Request for JDK-8160943 : [PIT] new failure of closed/javax/imageio/ReadAllThumbnailsTest.java

[Jim Graham]

I think this is fine, but I noticed that some of the recently added comments have some grammar issues.  It might be nice 
to change the following:

 565                     // markers which do not contain length data
(doesn't => do not)
 576                     // markers which contain length data
(contains => contain)

I don't need to review those changes...

                        ...jim

On 7/12/16 9:15 AM, Jayathirth D V wrote:
Hi,



Thanks for your input Phil.

I have made changes just to parse “FF FF”(Like “FF 00” or any marker without 
length)and not consider it as an invalid
marker in skipImage() of JPEGImageReader.java.

Also I have removed closed/javax/imageio/ReadAllThumbnailsTest.java from 
ProblemList.txt as part of fix.



Bug : https://bugs.openjdk.java.net/browse/JDK-8160943



Please find webrev for review for JDK9:

http://cr.openjdk.java.net/~jdv/8160943/webrev.00/



Thanks,

Jay



*From:*Phil Race
*Sent:* Saturday, July 09, 2016 12:37 AM
*To:* Jayathirth D V
*Cc:* Jim Graham; 2d-dev
*Subject:* Re: REG : JDK-8160943 : [PIT] new failure of 
closed/javax/imageio/ReadAllThumbnailsTest.java



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