[Pan-users] Re: Previews gone screwy

[Duncan]

Dave Chand <address@hidden> posted
address@hidden, excerpted below, on 
Fri, 19 Oct 2007 23:39:25 -0400:

> On Oct 6, 2007, at 6:58 PM, Greg Lee wrote:
> 
>> Is it the decoding? When I save the decoded jpeg files with Pan and
>> view them with a different viewer program, they seem perfectly okay.
>>
>> I looked at the two image files that stevem refers to, and I get the
>> same results as he: "Denali Sunrise" at 298559 bytes (as reported by
>> Pan) views ok, but "Lake Pend Oreille" at 423726 bytes displays
>> incorrectly.
>>
>> I looked at some other 1 part images in this same newsgroup and found
>> that all those with byte size <= 369052 displayed correctly, but all
>> those with byte size >= 369361 displayed incorrectly.  Of the two dozen
>> or so that I tried.
> 
> I have been experimenting with gdk-pixbuf. What I find is the following:
> in the file gtk+2.12.x/gdk-pixbuf/io-jpeg.c there is the statement
> #define JPEG_PROG_BUF_SIZE 65536
> if you change its value to something significantly higher, such as
> #JPEG_PROG_BUF_SIZE 500000
> then it seems the decoding problems go away.
> 
> Can someone with some knowledge of gtk please comment on this?

That sounds reasonable.  (Not that I've any specific authority on the 
matter, or even really know what I'm talking about, but, it /does/ "sound 
reasonable" =8^)

BTW, missed it before, but I used to live up in NE Washington state, by 
the "Pend Oreille" river.  It's pronounced "pond o-ray", and yes, it's 
/very/ beautiful (and relatively remote) up there.  That was back in the 
early 80s, but the entire county had a sum total of 8000 people in it.  
The county is long and skinny, and about 5000 of those 8000 were in the 
southern third.  The rest are concentrated around the river/highway/
railroad that threads its way down from Canada, probably a strip two 
miles wide.  The rest of the county is/was /very/ sparsely populated, 
with much of it being US Forest Service land.  There were two towns in 
the northern part of the county, Ione and Metaline Falls.  Ione had a 
timber mill, Metaline Falls had a Portland Cement quarry and processing 
facility.  That and the US Forestry Service and retirement were pretty 
much the sole sources of income for the area, all 3000 or so people in 
the northern 2/3 of the county.

Wow, it has been quite some time since I'd seen that name.  It sure 
brings back memories! I never would have expected to see it here! =8^)  I 
wonder how much things have changed...

-- 
Duncan - List replies preferred.   No HTML msgs.
"Every nonfree program has a lord, a master --
and if you use the program, he is your master."  Richard Stallman