Hi Jay,

How did you generate that image with thumbnail?  With ImageIO?

                        ...jim

On 07/19/2016 12:18 PM, Jayathirth D V wrote:
Hi Phil,

I generated Jpeg image with thumbnail as given in test case attached for 
https://bugs.openjdk.java.net/browse/JDK-4958271 with JDK 9.
The image has only two APP0 markers and after the second marker it has "00 FF" which we can 
consider as "X FF" as per https://www.w3.org/Graphics/JPEG/itu-t81.pdf. But it is just continuation 
of pattern "00 00 FF" which we see around the end of second APP0 marker.

For this new image I don't see whether we are writing improperly in JDK9(If we consider 
"X FF" bits between markers).
So we can just apply http://cr.openjdk.java.net/~jdv/8160943/webrev.00/ and 
open up the test case(after verifying whether it is the only test case which 
uses this particular image) with new image that I have created.

Thanks,
Jay

-----Original Message-----
From: Philip Race
Sent: Wednesday, July 13, 2016 10:06 AM
To: Jim Graham
Cc: Jayathirth D V; 2d-dev
Subject: Re: [OpenJDK 2D-Dev] Review Request for JDK-8160943 : [PIT] new 
failure of closed/javax/imageio/ReadAllThumbnailsTest.java

Whilst looking at the reason this test was originally created
https://bugs.openjdk.java.net/browse/JDK-4958271
it started to look likely that the image was (as I sort of suspected) was 
generated by IIO itself.

I think there a couple of things we can do here
1) Open up the test (and image - although if moving it make sure no other tests 
in that location need the image).
2) Investigate to see if the bug such that the "bad padding" is written out is 
still reproducible with current IIO ... or if it was fixed sometime between when that 
image was created and now.

-phil.

On 7/12/16, 7:48 PM, Jim Graham wrote:
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



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