Strange alpha channel behavior in jscroll pane

Hi,
My first post here.
I have been strugling for a while with a problem with alpha channel opacity and scrollpane. I basically have a JScrollpane that contains a JPanel with JLabels. The JLabels have a mouse action that changes their background to higlighted by using a color with an alpha channel.
When a mouse is over a JLabel we call:
public void mouseOver(){
          this.setForeground(Color.WHITE);
          this.setBackground(new Color(100,100,100,100));
          this.setOpaque(true);
This works but with some strange rendering problems. Sometimes the "background" shows other parts of the screen insted of the correct background. This is kind of hard to explain so I took a screen shot that elaborates this.
The correct behavior:
http://www.rulli.org/~mravimo/seka/correct.jpg
The wrong bahavior:
http://www.rulli.org/~mravimo/seka/wrong.jpg

I think there seems to some abuse of the 'opaque' setting in Java. Opaque, literally, of course, describes something through which nothing can be seen (if you can see through it, it's either translucent or transparent). That means alpha 0 is transparent, alpha 255 (for an 8-bit channel) is opaque, and anything else is translucent.
ComponentUI uses 'opaque' to determine whether to paint the component background. This is where the semantics are broken: it should really query the background color to see if it's non-null and its alpha is non-zero, thus painting translucent colors as well as opaque. I think there is a good case for this being a Java bug if it's not already - though I'd anticipate the counter-argument being that it will raise issues with backward-compatibility ("if it's been broken long enough, don't fix it").
The problem you're seeing, I suspect, is due to the same flag being used (semantically correctly) to help optimise the paint process (if something really is opaque then there's no point rendering underneath it).
Unfortunately, fixing ComponentUI is a non starter since it can only be fixed by extension (multiply the number of components by the number of L&Fs and you're on your way).
As a workaround you can extend JLabel and override paintComponent(); or plug in a specific label UI which fixed the ComponentUI problem; in both cases leaving the opaque setting at false.

Similar Messages

Unexpected Alpha channel behavior in Premiere

Is there no way to interpret alphas as straight versus premultiplied in Premiere? Why do my transparent layers and clips with alpha channels display differently with a Black Video layer below them?
Background info:
I'm exporting my film to files with codecs that support alpha channels, not because I want an alpha in the result but because I need full RGB / 444 color coding for digital cinema theaters. I'm using ProRes444, Targa and PNG Image sequences to preserve as much quality as possible in my master exports.
I've discovered that there is no option to disable the alpha transparency in the Export Media step while preserving at least 10 bits per color channel (Trillions of colors in AE).
To solve this problem, I've had to add a "Black Video" clip to the first video track, underneath the film's content. When this is done, the pre-rendered text elements with alphas look different. They are movie trailer style text treatments that are light text over pure black. (I'm on my ipad right now and don't see a way to upload screen shots to show examples)
The result with the black video layer applied at the bottom is similar to the way QuickTime 7 displays straight alphas incorrectly. This problem occurs with both straight and premultiplied renders. The rendered text is from after effects and is stored using the animation codec.
I'm aware of how to work around this, by maintaining the alpha transparency in Premiere and then removing the alpha channel of my export by running it through After Effects, but that is a ridiculous, time consuming step.
I'm working with the GPU Mercury Engine on with a K5000 from NVIDIA. Can anyone explain this behavior? Is there no way to interpret alphas as straight versus premultiplied in Premiere? Why do my transparent layers display differently with a Black Video layer below them?
Here are the screen shots
UNDESIRED EFFECT using Black Video layer at bottom: Notice the fuzzy glow surrounding the text. This is happening with both straight and premultiplied renders.
INTENDED LOOK when composited over nothing: The glowing edges are displayed the same way in Premiere as in After Effects.

In my understanding, the reason 444 is indicated is because they are not RGB codecs. They simply sample the same amount of color as is possible in true RGB codecs. They still require a conversion from RGB to YUV for coding to a file, which almost always introduces a very slight shift in values, though usually imperceptible or acceptable. If the codec is truly RGB there is no need to indicate luminance vs color sampling.
...I think.
Again thank you for your awesome input! You've been a huge help here on my day off. :)

On export, strange color bleeding/alpha-channel-ish problem but no alpha . . .

I'm hoping someone can shed some light on this. When I tried to export a project from Premiere today, I got some unwanted rainbow colors on the white text. The video clip was made in After Effects. I assumed that I must have been caused by an alpha channel (as I think I have seen something similar to this before with alpha screw ups), or some other unusual setting. But codec is straightforward and frequently used (Avid HD). The file from AE looks fine. It looks fine on the Premiere timeline. Only the export from Premiere is screwed up. Every codec I tried - H.264, MP2 . . always the same issue. The only type that didn't screw it up was DV AVI. But this is SD resolution is no good for me; it was just a test. Does anyone have any ideas what may have caused this.

Still no ideas?
I imported another clip, rendered in a different after effects project. I also copied it into new sequences with new sequence settings. I'm still getting the same thing! HELP!

Alpha channel videos problem on AIR 3.8 beta Android

Hi, I've found a strange behavior on the beta 3.8 SDK. When I load and play a FLV video with alpha channel it becomes completely black, but if I re-load it, it shows well. This does not happen on applications created with the release, 3.7 version of the SDK.

I think I am encountering the same issue with Air 3.8. Although I am not using the alpha channel and the video is a quicktime (.mov),
the video appears black (I can hear the audio playing).
I cannot switch back to 3.7 because that gave a error uploading the apk to the new google play console because of signing issues,
the upload issues were fixed in 3.8.

More CS 5 - ProRes 4444 Alpha channel nonsense

Hi:
Quicktimes I render out of After Effects CS 5 using the ProRes 4444 codec are tagged as having an alpha channel even though my settings in the Output Module are RGB and Trillions of Colors. NOT RGB + Alpha and Trillions of Colors+. It doesn't matter whether my project is 8 bit or 16 bit.
When I bring such movies back into AE it shows them as having an alpha channel (Trillions of Colors+). If I do a Get Info in QT player it shows Millions of Colors+, and FCP shows them as having an alpha, too.
I just upgraded to Snow Leopard 10.6.8 (figured it was safe after two years) and in the process switched full time to CS 5 (I only used it in the past to open other's projects). I never had these issues with CS4. I have not installed any AJA codecs into this new OS (clean install over wiped HD).
This appears to be the opposite of the problem most have been having, which is AE won't generate an alpha in ProRes 4444 without moving codecs and other nonsense.
The reason this is a problem is because when I bring these Quicktimes with faux alphas into FCP for editing I can't export a reference movie. FCP rewrites the whole timeline.
Haven't these CS 5/ProRes 4444 codec/Alpha channel issues been going on for over a year? Do I have to buy CS 5.5 to get this to work correctly?
Thanks.
Shawn Marshall
Marshall Arts Motion Graphics

PR422HQ is way overkill for 99% of the video and film producers in the world. It's there for a specific elite of the entertainment biz, those who work in 4k on 64bit systems, I guess, that' ain't me! It's one of those "if you have to ask, you can't use it" sort of things. Anyone who uses the advanced features of the ProRes family knows why. That's the theory. In my practical experience over on the FCP forum at Apple, 99% of those using ProResHQ believe they are improving their original footage.
Apple ProRes 4444
The Apple ProRes 4444 codec offers the utmost possible quality for 4:4:4 sources and for workflows involving alpha channels. It includes the following features:
Full-resolution, mastering-quality 4:4:4:4 RGBA color (an online-quality codec for editing and finishing 4:4:4 material, such as that originating from Sony HDCAM SR or digital cinema cameras such as RED ONE, Thomson Viper FilmStream, and Panavision Genesis cameras). The R, G, and B channels are lightly compressed, with an emphasis on being perceptually indistinguishable from the original material.
Lossless alpha channel with real-time playback
High-quality solution for storing and exchanging motion graphics and composites
For 4:4:4 sources, a data rate that is roughly 50 percent higher than the data rate of Apple ProRes 422 (HQ)
Direct encoding of, and decoding to, RGB pixel formats
Support for any resolution, including SD, HD, 2K, 4K, and other resolutions
A Gamma Correction setting in the codec’s advanced compression settings pane, which allows you to disable the 1.8 to 2.2 gamma adjustment that can occur if RGB material at 2.2 gamma is misinterpreted as 1.8. This setting is also available with the Apple ProRes 422 codec.
Apple ProRes 422 (HQ)
The Apple ProRes 422 (HQ) codec offers the utmost possible quality for 4:2:2 or 4:2:0 sources (without an alpha channel) and provides the following:
Target data rate of approximately 220 Mbps (1920 x 1080 at 60i)
Higher quality than Apple ProRes 422
Apple ProRes 422
The Apple ProRes 422 codec provides the following:
Target data rate of approximately 145 Mbps (1920 x 1080 at 60i)
Higher quality than Apple ProRes 422 (LT)
Apple ProRes 422 (LT)
The Apple ProRes 422 (LT) codec provides the following:
Roughly 70 percent of the data rate of Apple ProRes 422 (thus, smaller file sizes than Apple ProRes 422)
Higher quality than Apple ProRes 422 (Proxy)
Apple ProRes 422 (Proxy)
The Apple ProRes 422 (Proxy) codec is intended for use in offline workflows and provides the following:
Roughly 30 percent of the data rate of Apple ProRes 422
High-quality offline editing at the original frame size, frame rate, and aspect ratio
High-quality edit proxy for Final Cut Server
The Apple ProRes family of codecs provides these advantages:
Quality indistinguishable from that of the most pristine sources: Maintains superb quality even after multiple encoding/decoding generations.
Mastering-quality 4:4:4:4 RGBA: Provides a lossless alpha channel with real-time playback (Apple ProRes 4444 only). Mastering-quality 4:4:4 Y′CBCRcolor and 4:2:2 Y′CBCR color are also available.
The quality of uncompressed HD at data and storage rates lower than those of uncompressed SD: Provides real-time editing performance comparable to or better than that of any other HD codecs in Final Cut Pro.
Apple ProRes encoding at any frame size—SD, HD, 2K, 4K, or other: Apple ProRes codecs can also be encoded into nonstandard frame sizes, but nonstandard frame sizes are not supported for real-time playback in Final Cut Pro.
Variable bit rate (VBR) encoding: “Smart” encoding analyzes the image. Efficiency is increased because excess bits are not wasted on simple frames.
10-bit sample depth: Preserves subtle gradients of 10-bit sources (sunsets, graphics, and the like) with no visible banding artifacts. When you import a file using an Apple ProRes codec, you don’t have to first determine whether the file is an 8-bit or 10-bit file. Apple ProRes codecs always preserve the bit depth of your original source files.
I-frame–only (intraframe) encoding: Ensures consistent quality in every frame, with no artifacts from complex motion, and speeds up editing.
Fast encoding and decoding: Delivers high-quality, real-time playback and faster rendering times.
Equipment affordability: Because of low bit rates, you can edit more streams with more real-time effects on slower drives, or have more users accessing the same media over shared storage devices.
Workflow options for any video format that does not have native Final Cut Pro support: The Apple ProRes format provides an effective workflow for projects involving multiple acquisition formats when you want to standardize on a single codec.
Better rendering for native editing: Can be used to render long-GOP MPEG-2 formats (such as HDV and XDCAM HD) to speed up editing and avoid MPEG-2 reencoding artifacts before output.

Resolution, audio, alpha channel, and backup questions (newbie)

Hello!
Well, after a few weeks of fidgeting around with FCE, I've come up with quite a few questions:
Image/Audio questions
A. What is the best still image size for import to a NTSC DV movie? Is it the 720x480 px (3:2 aspect ratio) standard of the DV image, or the 4:3 ratio of your generic CRT TV?
I know it depends on pan/zoom. This brings up the next question:
B. I have a still image - literally a blue and black two-color image - that I'd like to zoom. It will start out with a very close shot - and zoom out until it takes up around 10% of the screen. The ending frame (the DV size) will be about 10-12 times smaller than the original image. Does this mean that I should make the original 10-12 times bigger (in both directions) than a DV frame?
This clip is essentially an imitation of the opening of the movie "Home Alone", where the screen begins blue, and as it zooms out, you see it's a stylized house, which zooms out to a tiny size. That's essentially the effect I'm going for.
Audio/Video sync issue
C. Some of the clips I've imported from old iMovie projects are a little out of sync. It's not a conversion issue, but an issue with bad editing on my part . So, I have a still image that's about 1.5 seconds too short - it cuts to the next still, which is 1.5 seconds too long. I've added edit points at both ends of the out-of-sync clip, so that I have a 1.5 second clip, with its own audio and video.
The problem is that the audio is perfect, but the video is bad. So, I need to replace the video, without changing the audio. How is this done?
D. Sometimes, I'll end up with either audio or video that's not quite right after importing a movie. However, FCE locks them together. Is there a way to unlock them so that I can change either? Essentially, is there a way to change the audio and video from one clip into two seperate clips?
E. Can I export a single clip or two only? (eg - the same as the "Share selected clips only" check box the iMovie's share menu)
Alpha channel/marquee question:
In one idea I had for this short, I have a still image (and some video) where I'd like to highlight a small area in one part of the image. In one part, it's a small object in the background that I'm highlighting. If you've seen a documentary where they have a group photo, and highlight the face of one particular person, that's the effect I'm going for.
I've made some Photoshop images that can achieve this effect - using a transparent background, a black top layer (at ~40-80% opacity), and an eliptical marquee for the highlighted portion. I then import it, and fine tune the location/size. It works, but it takes a lot of time to talor each shot. Is there some way to do this IN Final Cut Express? A filter perhaps?
In addition: (alpha-video)
is there a way to turn part of a video into an alpha channel, so that it's transparent in the final movie? It's not so much a solid color (as the bluescreen/chroma key technique would need), but more of background. For example, I would like to take some footage of my family walking in front of trees, remove the background, and place an entirely different video/still in. Is that possible?
Backup: FInal question:
I have my source media organized fairly well on my external drive. However, if my drive should die, It would be incredibly tedius to re-link all the files. (I do have a fairly current backup of the external files). Not to mention finding the orignal capture files, re-timing the project, and so on. The project file itself is probably the easiest to back up.
So, how do you back up EVERYTHING? Some projects may have hundreds of files, all over my external drive. Is there some easy way to back up all the files into a single place, like a single folder or DVD, so that if my drive should fail, all the files are in one spot?
I can export them back to a miniDV tape, but I don't have that many, plus they're $5 a pop. I can do this with Toast, but I'll likely end up missing some out-of-the-way files. If only .Mac's Backup had a Final Cut preset.....
I know that's a BUNCH of stuff up there, so if you can help with any of them, i'd be appreciative.
Thanks,
Daniel
15" 1.67 Powerbook G4 (non-HiRes), Slot loading iMac DV SE Mac OS X (10.4.7) 1G RAM on PB, 384 MB iMac.

Try breaking these up into separate questions. Easier to answer and easier to be found by someone searching for answers to the same question.

Inconsistant alpha channel import on .mov files

I am creating a movie using animation I create in Maya which is then composed in Shake with some alpha masks and exported using the animation codec to a .mov file into Motion. In reviewing my workflow (I'm about midway through things) I recognized I had an error in my screen sizes from one tool to the next and while it was not too noticeable, I thought it best to correct. This is where I should have left dead dogs lie.....
Anyway, this is best described with the flow I show below:
Motion Project Setup on ALL file types
720x480, 8bit, NTSC D1/DV
Lower First (Even)
29.97 Fps
Background Color - Black
Background - Transparent
Case 1:
Maya__->_Shake___->Anim Codec_________>Motion 720x480
720x486->720x486-->_Mil+_Col-->foo.mov-->File squished 6 pixels in Y
but alpha is present
Case 2:
720x480->720x480-->_Mil+_Col-->foo2.mov->File is 8 pixels narrow in X
alpha channel is not preset
I open foo.mov and foo2.mov in shake and look at the files and the
size is as follows:
foo.mov - 720x486
foo2.mov - 720x480
BOTH .mov files have the alpha channel present and the data is correct.
Just for grins, I output a file sequence of .tif files from shake of the
foo2.mov files and verified that the alpha channel was present in
photoshop and then did an import into motion with the same results of
foo2.mov. Size is shrunk by 8 pixels in X and no alpha channel.
It appears at least that Motion is making decisions based upon the screen
size and importing or not importing the alpha channel.
Any thoughts would be very much appreciated.

Well, it is strange. Shake says it is 720 and for that matter so does Motion in the Media tab. Motion says it is 720x480 as does shake but when the clip is overlayed against the black background you can see 4 pixels on each side of the clip. The motion project file says it is 720x480 too.
UPDATE....
I just checked the motion file and deleted all of the media clips, but when I went to the media tab there was still one copy of the old 720x486 clip there. Every time and method I tried to delete it, it would crash motion. So, I copied all of the other text data I was using motion to generate, created a new motion project and pasted the text in. When I import the 720x480 file into the new project it lines up perfect. This must be a "feature mode" I must have gotten motion into.
Anyway, problem solved. Thanks much for your help Andy. I kept looking at this and not seeing the forest for the trees.
Much appreciated.

Sudden problem with importing tiff files with alpha channel (CS5)

OK this is driving me nuts. For years I have been importing image files that have an alpha channel into FCP as.tiff files. I use Photoshop files only when I want to use the layers as they are too cumbersome otherwise). I have recent upgraded Photoshop, etc. to CS5 and now FCP won't import them anymore. I get a message saying: "File error: 1 file(s) recognized, 0 access denied, 1 unknown"
I am not doing anything different and tiff files created in just the same way in an earlier version of Photoshop import and work just fine. Is this a CS5 bug? Does anyone know of a work around. I want to keep using tiff files as they seem to work best for me with alpha channel work (and I don't see why I need to reinvent the wheel).
Thanks
A

I've had a similar issue recently. Same TIFF files downloaded from the same server, different FCP project, new error. I either see"File error: 1 file(s) recognized, 0 access denied, 1 unknown" or I get the even stranger, "Unrecognized file type."
I can open them in PS and save them again as TIF, same results. I know these are not CMYK files but even if resave the TIF as RGB, I get the same results, they are not recognized by FCP.
But if I open them in PS and save them as PNG with alpha, they improt fine.
I have no idea what's going on.
bogiesan
Message was edited by: David Bogie Chq-1

Edit in Photoshop and Alpha Channel

When I open an image in Photoshop using 'Open with External Editor', and add an alpha channel, when I save it back to Aperture the alpha mask shows on top of the image, whether or not it is made visible in Photoshop. Furthermore, the thumbnail shows the mask as white and the image shows the mask as black.
Are others seeing this same behavior? Do I have a setting that is incorrect?

Search the discussions on a couple of these terms -- there was a thread or two a couple of months ago.
It turns out (I can't remember who pointe this out! sorry!) that if you put a completely blank alpha channel at the top of the stack of them (that is, under the R, G and B channels in the Channels palette), then save, the image shows up OK.

Alpha Channel in Photoshop for iWeb instant Alpha?

Hi,
Recently i wish to Make a Picture's Background to transperence.
I try to use a ODD color (green screen's GREEN) as background color so that it'll be easy to delete the background when apply the instant alpha function...but i relize that it doesn't really make sense at all...Most of the parts doesn't process well...
Question:~
+ What s'ld i do in Photoshop before i bring the picture file into iWeb for instant alpha?Alpha Channel and save as .psd?
+ Do any other useful way to solve the issue above?
Thanks!!

Here's what I do:
1 - open the file, double click on the background layer in the Layer pane to unlock it and add a second layer below the original layer.
2 - using your tool of choice delete the background you want removed. If the background is a single color I use the Magic Wand tool. You may have to work with the Tolerence number if there's any gradiants. Other wise I use the Quick Selection tool (again you may have to set the Tolerence level)
3 - When he background is removed you then use the File->Save for Web and Devices option.
4 - in the next window select PNG8 under Preset and check the Transparency box. Colors is set to 256, Dither at 200% and Web Snap 0% (these are all the defaults the first time I used it).
5 - The background should show transparent. It it doesn't click on the color that you want transparent in the Color Table and then click on the far left box in the toolbar directly below the color chart. You can add additional colors if desired.
6 - Save and you're done.
OT

Alpha Channel errors

Hello,
I'm working with some uncompressed Quicktimes in Final Cut 6 that have built in alpha channels, but they are not working properly when placed over other footage in my timeline. I just get a black background where the video from the track below should be appearing.
The strange thing is I've used these exact same quicktime's successfully in Final Cut 5, but now they aren't working. Also, when I view the clips alpha channel in the preview window the alpha channel displays correctly.
Does anyone know what's going on?

I'm just guessing... but in maybe it has something to do with your settings in the canvas window. Those three buttons across the top of the window- click on the one on the right (looks like a little square thingy) and make sure you have alpha + RGB selected. Maybe that'll do it.

How do I prevent the image from shearing when I have an alpha channel?

I'm using After Effects to prepare some videos for the web. They are running at 320x240. The settings are Flv/F4v, Millions of colors, 15 FPS, RGB and Alpha, 44K/16bit Mpeg III audio, CBR 1 pass with a bit rate of 872, On2VP6 encoding.
I create the alpha channel from a greenscreen behind the actor using standard keylight and garbage mattes.
When I do not encode an alpha channel, the image is fine. My problem is that when I try to encode the alpha channel, the image shears to the left from bottom to top, and the whole image is transposed about 40% to the left. But we need the alpha channel.
This is what the shearing looks like. Any ideas on what is happening and how to prevent it? Thank you.

To check the clip, I made a small swf file the same dimensions and frame rate, 320x240 @15fps. It's a single frame, single layer with no skin. It just plays the flv file when you open up the swf. The flv file is external, so to test the results, I just keep rendering in AE to the same flv file name.
The first two seconds play okay. The shearing doesn't begin till after that. So I'm suspecting there is something strange with the keyframes. I even tried messing with the keyframe distance settings at 30 and 15, without effect.
The original video is an 854x480 mov file playing at 14.99 fps, millions of colors, Sorenson 3 coding. When I bring it into the comp, which is set at 320x240 @15 fps, I scale the movie to 50% in size. At your suggestion, I just tried making sure that all the frame rates are 14.99 instead of 15. Sadly, without any benefit. I'm still baffled.

Can't render an alpha channel in Compressor

This has allways been a problem for us.
Whenever I try to compress a sequence using compressor (2.0.1 on a 2Ghz G5 OS 10.4.8) and render an alpha channel it never works.
Typically I'll send a sequence containing only a lower third over a transparant screen to compressor, select the Amination + Alpha codec (all the settings seem correct: Animation, million of colors+, best quality) and I end up with the lower third over a black screen, no alpha channel. Also, if there is blank space in the timeline between clips that also renders as black, not transparant.
The strange thing is that when I export using Quicktime Conversion with the same Animation+Alpha settings it does work and I get nice clean transparancy.
Is this a bug with Compressor or am I missing something?
2.0Ghz G5 Mac OS X (10.4.8)

Mikey & Jumpy,
Compressor does have a Animation Alpha Preset under Motion Graphics and after reading this post for several days i decided to test it for myself and sure enough, I can't get it to work. I've exported the same lower third through Quicktime Conversion and through Compressor. Bring them both back into FCP and compare the format in the browser. They match exactly except for the Compressor version doesn't have the alpha in the time line. I tried exporting a ref and importing that into compressor, same result. I tried importing the new file into After Effects to see if it would interpret different, same result.
The only conclusion i can come up with is the Compressor is writing an alpha channel, but its also writing a black matte in the RGB. But as far as I'm concerned I can't see a discernible difference between QT Conversion and Compressor exports.
Good Luck
Chris

How to import an alpha channel from .PSD file?

I have a photoshop file (.psd) with an alpha channel. When I import this file into AE, I do not see the alpha being available or perhaps I don't know how to find it. I've followed this instruction but nothing happens afterwards. Okay, so my question is, when I drop the .psd file into my comp, how or where do I enble the alpha channel?

I am not sure this a bug.
It could be. But note that I can produce an identical case in which this behavior is not a bug.
The thing is, in the world of video applications, Alpha Channel means "fourth channel used to store transparency values".
In Photoshop, it normally means the same thing, but it can also mean "arbitrary channel created and stored for whichever reason the user may want it on the future". Typically, to save a selection so that it can be retrieved later. In fact, you can have many of these arbitrary channels.
So, imagine this scenario:
1. User makes a selection of the outline of the house.
2. Instead of cutting the pixels outside the house, or creating a layer mask, the user goes to the Channels panel and hits the "Save selection as channel" button (or equivalent menu command).
Photoshop creates a fourth channel (or even a fifth or a sixth if there were additional channels already), which is called "Alpha" but the user never did anything to make the information in that channel produce transparency.
If after making the selection, the user would have cutted pixels or created a layer mask, then that operation would be relfected on what we normally consider as Alpha channel.
In this case, what you can do is go to channels pannel, control click the thumbnail so that the channel is loaded as selection, then create a layer mask (Layer > Layer Mask > Current selection) from that selection. That's it.

Photoshop not presenting alpha channel as expected (like I'm seeing GIMP does)

Greetings,
I have a need to edit the channels independently (the values in my image mean things numerically rather than just what it looks like visually - so I need to edit the grayscale values in each of the R - G - B - and A channels seperately).
I've searched through google and other forum posts and others bring up the concept of not understanding alpha versus transparency - but I have yet to see an explanation that fully explains what I'm experiencing.
The closest was http://forums.adobe.com/message/2563436#2563436 But while I saw the exact same symptoms being described, the specific question was never really answered.
Hopefully, a concrete example with pictures will be able to communicate the issue and solicit a useful explanation and/or solution.
While, I'm specifically working with an RGBA image, below is a screenshot of a PNG that demonstrates the exact same behavior or symptom. The screenshot below represents the PNG inside GIMP and PS CS4. BTW, if you'd like to see or play with the image yourself, you can grab the same image at http://www.libpng.org/pub/png/img_png/imgcomp-440x330.png
GIMP, interestingly enough loads the PNG as expected - I see the transparency of the image treated as a true alpha channel.
In PS CS4 however, the transparency seems to be somehow embedded in the Red - Green - and Blue channels; but NO seperate alpha channel.
I can create the alpha channel through Select - Load Selection - Layer 0 Transparency - and pasting that into a newly created alpha channel - but the color channels still have the transparency mixture symptom - rather than showing the JUST the color component of that channel. (Note the channel differences of the GIMP's Red Channel versus PS's Red Channel - Said in another way, the yellow ball in the upper left of the image should have a red value of 255, so the Red Channels grayscale upper left ball should be white like it is in GIMP, rather than Gray as it is in PS).
I never thought I'd experience GIMP being superior to Photoshop - so hopefully somebody can shed light on what is going on - what configuration I may have myself in - or a process to get the channels seperated out in the manner I wish to work with them. Furthermore, maybe somebody can educate the Photoshop community what the difference between transparency and alpha[transparency] is. I haven't found quite the right explanation that makes the light go off in my head yet. As best as I have gleened "Alpha", which can be applied to any kind of channel, typically is in reference to transparency - and is applied as a document-whole transparency (as opposed to transparencies applied at a layer level - such as a layer mask).

I think I've finally determined that modern Photoshops have gone in a different direction that I feel "Alpha" should be done.
(good or bad).
Here are the steps and/or details of how I arrived at that conclusion.
If nothing else this has been very educational on how Photoshop treats alpha.
- Import your alpha'd PNG with SuperPNG format (see above on how to make sure you use the SuperPNG plugin to load the .png).
- In the SuperPNG dialog select "Alpha appears as seperate channel"
- Create a layer from the Background and Delete the original Background
(since the Background is locked and we can't edit the Background - we want to add a layer mask based on the alpha)
- Ctrl-Left Select the "Alpha 1" channel - Ctrl-C - and hit the "Add Layer Mask" button (square with the circle at the bottom of the LAYERS rollout)
- For this demo and clarity, I went ahead and deleted the alpha "Alpha 1" that came in through the SuperPNG plugin
So now I have the Layers like I kindof expected the main document to just come in as (kindof though - it is presented in a Layer Mask rather than Alpha Channel).
What is interesting - which you'll see if you toggle the layer mask on and off
(shift-click the mask thumbnail in the layer)
Note how the thumbnails in the channel views render differently during the toggle.
When the mask is off you see the individual color channels like I expect - black where there is an absence of that color.
However when you enable the layer mask - the individual color channels show in semi-transparent/checkerboard.
So this is exactly how the color channels are presented when loading in a .png (WITHOUT the SuperPNG plugin) or an .rgba
..you get the semitransparent views of the color channels - BUT the difference is - you have no way to directly see or edit the Alpha channel.
nor are the color channels represented as completely opaque versions.
What is really interesting - it is there though - if you Ctrl-Left Select the layer, Ctrl-C, and "Add Channel Mask" - you'll get the Alpha mask.
HOWEVER, the big issue is that you can't toggle or edit the Color-Channels like the Layer counterpart above;
they are ALWAYS the semitransparent/checkboard version; AND now we basically are double applying transparency
(due to the still embedded alpha/transparency AND the newly create "Alpha 1" channel)
I think this a bug (or a poor reimplementation of modern Photoshop releases; I believe older Photoshops used to break out Alpha in the "arguably correct" way - and in fact the way GIMP currently does).
Or maybe there are other explanations - like abstracting some of this complexity away from less advance users, etc?
So the SuperPNG plugin was useful in experimenting, understanding, and demonstrating what is going on.
However, if I'm trying to read in .rgba directly, I don't think I have a way of making the "Alpha appear as a seperate channel" as I think any image with "alpha" component should.
(png, tiff, rgba, etc).

Strange alpha channel behavior in jscroll pane

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