[Chameleon] Setting quality for JPEG output
Paul Spencer
pspencer at dmsolutions.ca
Mon Jul 11 06:07:15 EDT 2005
Tyler,
"auto" is a 2.2 thing AFAIK, but Julien should jump in here an comment :)
Chameleon doesn't do anything magical with your imagetype from its
configuration file. It calls the mapscript function selectOutputFormat.
Your block in the map file just sets up options for that driver.
We'll need to take a look at this and see exactly what happens, but my
understanding is your definition of the output format should take over.
Cheers
Paul
Tyler Mitchell wrote:
>>The reason for this, and other choices like the xml theme legend
>>wms_name thing come from Chameleon's roots as an OGC-specific tool
>>that
>>only worked with Context files. In a context file, there is no
>>place
>>for image format and no way to set layer names. So even though
>>Chameleon used a map file, we had to provide an alternate way to
>>handle
>>these types of issues.
>
>
> Thanks Paul, I totally understand and am happy to see it get pushed beyond OGC specs :)
> I still don't really believe that Chameleon will look for the imagetype from my map file though. I've done a few tests where I have image_type = JPEG in my config/chameleon.xml file. Then, in my map file I set:
>
> OUTPUTFORMAT
> NAME JPEG
> DRIVER "GD/JPEG"
> MIMETYPE "image/jpeg"
> IMAGEMODE RGB
> EXTENSION "jpg"
> FORMATOPTION "QUALITY=65"
> END
>
> If I change QUALITY=xxx it doesn't affect the output all. I also created a new format name "jpeg_q100" and put then in for image_type, but Chameleon bailed and didn't know what I meant. What am I missing? Do I need v2.2 to do this?
>
> Jacob also mentioned "AUTO" but that fails. I'm working on upgrading to 2.2, will that help?
>
> Tyler
>
>
>>Some changes could be made to make a non-OGC method easier to work
>>with
>>but it means some work to go back and undo the code that makes
>>these
>>assumptions.
>>
>>HTH
>>
>>Paul
>>
>>Tyler Mitchell wrote:
>>
>>>Thanks Jacod and Jason for the response. I'm now hopeful. I
>>
>>haven't liked having a "site-wide" setting for image_type, so this
>>solution has been most helpful. I'm still a bit skeptical that my
>>map file settings are being picked at all - but I'll get over it :)
>>
>>>Tyler
>>>
>>>----- Original Message -----
>>>From: Jacob Delfos <jacob.delfos at maunsell.com>
>>>Date: Friday, July 8, 2005 10:53 pm
>>>Subject: RE: [Chameleon] Setting quality for JPEG output
>>>
>>>
>>>
>>>>Hi Tyler,
>>>>
>>>>The imagetype set in chameleon.xml will determine what is being
>>>>used,
>>>>but it still listens to the settings in the mapfile. So if you
>>>>want a
>>>>jpeg with 60% quality, then you have to specify the quality
>>>>setting in
>>>>the output format, like this:
>>>>
>>>> OUTPUTFORMAT
>>>> NAME jpeg
>>>> DRIVER "GD/JPEG"
>>>> MIMETYPE "image/jpeg"
>>>> IMAGEMODE RGB
>>>> EXTENSION "jpg"
>>>> FORMATOPTION "QUALITY=60"
>>>> END
>>>>
>>>>I think with the current setting of "auto" for image type, it
>>
>>will
>>
>>>>use
>>>>the imagetype setting in the mapfile as mapserver would do.
>>>>
>>>>The customisation I posted was for chameleon version 1. I have
>>>>changed
>>>>it a little to automatically detect whether a raster exists in
>>
>>the
>>
>>>>layers being drawn (while also using the "forcejpg" parameter in
>>>>the
>>>>metadata), and to switch to jpeg based on that. Let me know if
>>
>>you
>>
>>>>want
>>>>me to send it to you.
>>>>
>>>>regards,
>>>>
>>>>Jacob
>>>>
>>>>
>>>>
>>>>-----Original Message-----
>>>>From: chameleon-bounces at lists.maptools.org
>>>>To: Jason Grimes
>>>>Cc: Chameleon User List
>>>>Sent: 7/9/2005 1:00 PM
>>>>Subject: Re: [Chameleon] Setting quality for JPEG output
>>>>
>>>>Hi Jason,
>>>>In traditional MapServer applications, I've done it several
>>
>>using the
>>
>>>>method you mentioned. Are you saying that Chameleon actually
>>>>checks the
>>>>IMAGETYPE from the map file? I don't think so. It ignores it
>>
>>on mine
>>
>>>>and relies on the config/chameleon.xml image_type setting which
>>
>>is
>>
>>>>usedat map drawing time in the drawmap.php scripts. As far as I
>>>>can tell,
>>>>the only valid values for that setting are specific formats that GD
>>>>supports and not related to the map settings for IMAGETYPE. My
>>>>questionis really how to specify a quality setting for the
>>>>image_type that
>>>>Chameleon uses, not how to set it in the map file. If that
>>
>>makes any
>>
>>>>sense...
>>>>
>>>>Am I'm going mad or is this tricky for everyone else too?
>>>>
>>>>Tyler
>>>>
>>>>----- Original Message -----
>>>>From: Jason Grimes <jgrimes at gi.alaska.edu>
>>>>Date: Friday, July 8, 2005 3:40 pm
>>>>Subject: Re: [Chameleon] Setting quality for JPEG output
>>>>
>>>>
>>>>
>>>>>Hi Tyler,
>>>>>
>>>>>You set this with FORMATOPTION in the OUTPUTFORMAT block of
>>>>
>>>>your map
>>>>
>>>>
>>>>>file. Here is what I have mine set to...
>>>>>
>>>>> IMAGETYPE jpeg
>>>>> IMAGECOLOR 255 255 255
>>>>>
>>>>> OUTPUTFORMAT
>>>>> NAME jpeg
>>>>> DRIVER "GD/JPEG"
>>>>> MIMETYPE "image/jpeg"
>>>>> IMAGEMODE RGB
>>>>> EXTENSION "jpg"
>>>>> FORMATOPTION "QUALITY=100"
>>>>> END
>>>>>
>>>>>The IMAGETYPE must match the NAME in OUTPUTFORMAT.
>>>>>
>>>>>Jason G
>>>>>
>>>>>On Fri, 2005-07-08 at 11:20, Tyler Mitchell wrote:
>>>>>
>>>>>
>>>>>>Jacob,
>>>>>>I just discovered your drawmap mods for setting imagetype based
>>>>>
>>>>>on layer
>>>>>
>>>>>
>>>>>>metadata -- very good!
>>>>>>http://lists.maptools.org/pipermail/chameleon/2004-
>>>>>
>>>>>August/001253.html> It is just what I have been needing.
>>>>>
>>>>>
>>>>>>Does anyone know if I can set the compression/quality for JPEG
>>>>>
>>>>>output?
>>>>>
>>>>>
>>>>>>I know how I'd do it in a map file, but $szImgType in
>>>>>
>>>>>drawmap.php seems
>>>>>
>>>>>
>>>>>>to only refer to image format, not sub-settings for that format.
>>>>>>
>>>>>>Can anyone give me some pointers?
>>>>>>
>>>>>>Tyler
>>>>>>_______________________________________________
>>>>>>Chameleon mailing list
>>>>>>Chameleon at lists.maptools.org
>>>>>>http://lists.maptools.org/mailman/listinfo/chameleon
>>>>>
>>>>>_______________________________________________
>>>>>Chameleon mailing list
>>>>>Chameleon at lists.maptools.org
>>>>>http://lists.maptools.org/mailman/listinfo/chameleon
>>>>>
>>>>
>>>>_______________________________________________
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>>>>http://lists.maptools.org/mailman/listinfo/chameleon
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>>>
>>>
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>>>
>>
>>--
>>+-----------------------------------------------------------------+
>>|Paul Spencer pspencer at dmsolutions.ca |
>>+-----------------------------------------------------------------+
>>|Applications & Software Development |
>>|DM Solutions Group Inc http://www.dmsolutions.ca/|
>>+-----------------------------------------------------------------+
>>
>
>
>
--
+-----------------------------------------------------------------+
|Paul Spencer pspencer at dmsolutions.ca |
+-----------------------------------------------------------------+
|Applications & Software Development |
|DM Solutions Group Inc http://www.dmsolutions.ca/|
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