[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
>
>
>