Alpha channel when not premultiplied

Hello,
I've got an image which has unassociated alpha channel (So each RGB sample isn't premultiplied with the corresponding Alpha sample).
I try to create a PDF so I create an XObject for my RGB samples, I add a soft mask for the Alpha stream and associate this Alpha with my main XObject.
When it's premultiplied I add a /Matte array for this soft mask but in this case I expected not to add one but without I get completely wrong output so I added it.
Is it possible to create a PDF without modifying my main image's data ? (without pre-blending)
In order to illustrate what I'm experiencing :
Expected output :
Current output :
Thanks for your help.

Thanks for the suggestion Teddy. We will add it to the list
of things to take a look at adding in a future release.

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No alpha channel when BCC lens flare applied

Hello
With the help of Andy Neil, I created a light sweep for a lighthouse logo. I added a BCC RT Lens Flare Adv filter to enhance the effect of the light sweeping past the viewer. I looked great.
Then I got to thinking that the lighthouse logo with light sweep would make a great lower third, so I scaled it down to logo bug size and superimposed it over a lower third background.
The problem is that the inclusion of the BCC Lens Flare filter seems to add a black layer over the entire movie so that the lower third cannot superimpose over my talking head. I know it's the BCC Lens Flare because when I deactivate the filter and export, the alpha channel is present and the lower third is superimposed over the footage.
I've tried exporting with Lossless+Movie Alpha and Animation,
My question: Can anyone tell me why this is happening and how I might be able to remedy?
Thank you,
Blake

Yes, the lens flare is the problem. The generator is rendered as a blend mode which blends only with the elements in the project. The blend doesn't export as transparency because a blend mode is only transparent when combined with another layer.
Here are your solutions:
1) Composite the lower thirds with the video in Motion. If the bkg layer is in Motion, then the ADD blend mode applied to the lens flare will work properly.
2) Create an alpha matte layer. This requires you to create a black and white image of your project that defines transparency for your lower 3rd. Export that as well, and then do a Composite Mode-Luma in FCP.
3) Apply a Luma Key to your lens flare before export. This works, but is imperfect because the filter will inevitably key out some of the not-so-bright aspects of the lens flare, leaving you with a diminished result.
4) (My Suggestion): Apply the lens flare in FCP. FCP contains the SAME lens flare generator used by Motion. This will give you the best possible result with the least amount of extra work on your part.
Andy

Tiff files with Alpha Channels do not display or print correctly...

I have Tiff files that have been edited in Photoshop that do not display correctly. As far as I can tell this is caused by the existence of Alpha channels in the channels panel in PS. When the files are imported to Aperture, they only display information from either the alpha channel or a layer using that alpha channel as a mask.
If this is true, what are people doing about it. This cant be acceptable???
Are there any work arounds and is apple addressing this problem?
Can anyone else confirm this?
I am using Aperture 1.1.2, OS 10.4.7 and PS CS. on a Dual 2GHz Power PC G5 with 4.5 GB RAM
Please note, these are NOT .psd files. I have read and am aware of some psd compatibility issues, and have checked the maximize compatibility in PS.
-Sol

Thank you for your response, I am trying to figure out what to do differently when we re-create the PDF so we don't have font issues when we combine. I don't want to keep recreating the problem, I am looking for a solution. Why does this happen? What settings do I tell other to apply on their Acrobat? Is the a font issue in Adobe? I found this on a Google search on the internet and can't seem to get it to work on XI PRO.
Embedding fonts into Acrobat 9 through Distiller:
Launch Acrobat.
Choose Advanced > Print Production > Acrobat Distiller.
Select Standard in Default settings.
Go to Settings and select Edit Adobe PDF Settings.
Select Fonts and in the font source window select the fonts you want to Add.
Click Save As and then OK.

Procedure for Integrating Alpha Channel when saving as .dds file

Hello,
I'll try to keep this brief but that may be tough...
One project I use Photoshop CS4 for is painting aircraft used with Microsoft Flight Simulator X (FSX). Here is some background for folks who aren't familiar with this.
Each aircraft is downloaded as a "Paint Kit". The kits look much like the "trees" that plastic aircraft model kit pieces come attached to (see picture below).
I paint and add layers onto the kit until the aircraft resembles the design I chose. The paint kit includes a background, base parts usually in white, and an assortment of layers adding physical wear, shading, lines and rivets you see on actual aircraft.
Additionally, the kit includes an RGB Alpha Channel and Specular Maps. In this application, the Alpha channel provides the reflectivity or gloss on the aircraft paint. The Specular maps provide a sheen much like the subtle reflections you see from a metal flake paint job when the sun hits it directly.
Once all painting and manipulation is complete, the kit is "cut" into specific sizes. Once the kit is cut, each section is saved as a DDS file using NVidia tools. The resulting DDS files are placed into folders within the main FSX program folder. The FSX program "assembles" the sections and processes the different layers and channels resulting in aircraft that are incredibly detailed and realistic.
My problem is I don't know how to properly integrate and preserve the Alpha channel during the "Flatten Image" and when saving the file as a dds file. As you can see in the "Layers" section in the picture, the Alpha channel is already made. I just don't know what to do with it to preserve it and ensure the reflectivity it provides is visible in the final product.
Any help is appreciated - what I need to know isn't what the alpha does, but how to properly integrate it into the final product. I've searched for this info for the last several days, but I've had no luck in finding specific information on how to do that. I believe it's one of those procedures that is so simple, everyone knows how to do it. I guess I'm the only idiot on the planet that doesn't know how... .
The paint kit can be downloaded at http://library.flight1.net/wp-content/plugins/download-monitor/download.php?id=1467 if you need it to answer my question or if you're just curious about it.
Thanks for your time and consideration.
Mark

I know nothing about Nvidia DDS file format or 3D. From you screen capture you have no Alpha Channel. You do have a normal layer named Alpha Channel with its visibility turn off. Why are you flatting ? When I use Save As and use the file type pull-down and select DDS format to save I get the Nvidia DDS save Dialog that I do not know how to use or understand the buttons options or pull-down menu items. The file instruction and its background make no does not seem to match up with the parts.
I think you have to read the documentation for the Nvidia DDS plug-in. and the normal map plug-in https://developer.nvidia.com/nvidia-texture-tools-adobe-photoshop

Slightly distorted aspect-ratio (and missing alpha channel) when copy/paste from Photoshop

Maybe this is an old topic (but I didn't find anything on google or this forum):
When I copy images from Photoshop to Flash, the aspect ratio of the bitmap gets distorted. A 728x90 Bitmap becomes 727.6x90 (and so on...). The dpi is set on exactly 72 on both programs. Is there any way to JUST get a 1:1 pixel copy? (except using another program like Irfanview as a "man-in-the-middle")
Although I selected "32 bit color w/alpha" in the clipboard settings of Flash, the alpha channel seems to get discarded when copying from Photoshop. Shouldn't it at least work with Photoshop? I mean, it's an Adobe product after all and maybe the most commonly used together with Flash.
Would just be nice if a copy-paste between PS and FL was an easier thing.
I know there can also be a pixel-aspect somewhere (like used for video productions and wide-screen), but I didn't find settings for that anywhere.
I still use Flash Professional CS5.0

I'm on windows7 with CS5.5 and transparency and size are copied over just fine. You answered what would be my first question, 72dpi. How about the image mode. Are you using RGB 8bit?
I've had lots of issues with the OS not handling transparency very well also, such right-click on an image on a website that you know is a PNG and has transparency, then paste it into photoshop, the transparency isn't saved.
The route that always works (but is a PITA) is of course to save it as a PNG with transparency and just import it.

Export for DVD with Animation codec without alphas channels not working?

I'm using FCP 5 with DVDSP. My FCP projects consist of quicktime movies that are using the Animation compressor (for lossless quality), and the movies contain alpha channels (thus they were rendered at Millions + colors to preserve the alphas).
This is my problem. I want to now export a quicktime movie to use in DVDSP with animation compression, so it is again lossless quality (obviously to presever the quality through these steps). But I do NOT want to preserve the alpha channels, because what I've learned is that when made into a DVD, the alphas are not preserved and the image looks wrong (as if without the alphas).
So I basically want to "flatten" the video, if there was some way.
I would assume the solution would be to, in FCP, export a quicktime at animation compression, but set to Millions for colors, and not Millions + (I was taught that the Millions + will preserve the alpha info).
Well, what's happening is when I set it to that, it renders, but then I get info on the movie in Quicktime and it says it has Millions + still. And thus, it looks wrong in DVDSP.
What is going on? Is this a bug in FCP?
Does anyone have an idea as to how to get around this. The only thing that has worked for me is to export the Quicktime movie with "none" for compression, but that's making the movie SO large that I can't work with it and it doesn't play right when I make the DVD.
I really appreciate anyones help on the matter. Thanks!
Brian,.
Quad-core 2.5 G5 Mac OS X (10.4.6) 30" Apple Cinema Display
Quad-core 2.5 G5 Mac OS X (10.4.3) 30" Apple Cinema Display

Thanks for the suggestions. I have not yet tried laying a solid black video track underneath to see what it does, but it seems like a good idea and I'll try it out to see what happens when I get back home.
I'll try to explain what I mean by the image looking wrong.
I'm picking up where another left off, so I'm not sure of how he cut the quicktime movie together; all I know is that they used alpha channels in Photoshop and After Effects to make the image looks the way they want it. This is a drawn character laid on a white background with a black frame around the entire image. It looks the way he wants it to in the quicktime movie, and this quicktime movie is 720x480, animation millions colors +, 24fps.
This movie, along with others of the like, need to be cut together in FCP and then put on a DVD with DVDSP. When I export it and it looks "wrong", what's happening is there is a black block behind the drawn character. The guy that made the movies in AE says that, that is what it looks like when the alpha channel is not working correctly.
To test things, I've changed the quicktime compression settings in the sequence settings. If I set it to anything that is not animation, I get that black block in the viewer. (Note though, that if I set it to animation, millions + or not +, it shows the alpha correctly both ways).
In FCP's user manual it says that if you're passing your movie on to a DVD, to use a high or lossless compression to keep the quality up, like animation or PhotoJPEG. For this reason, I haven't wanted to go to DV - especially with this type of image (graphic drawn shapes), it's easy to see a quality difference.
It really seems like there is a lot of voodoo involved with compression settings. As for now the best "fool-proof" solution I've found is to re-render the movie in After Effects at millions (not+) so that it won't contain the alpha channel info, and FCP seems to like that a lot more.
I just wish I could get FCP to work with the movies as they were because I'm having to re-edit everything to work with these new movies now.
Thanks again for the tips and insight.
Quad-core 2.5 G5 Mac OS X (10.4.3) 30" Apple Cinema Display
Quad-core 2.5 G5 Mac OS X (10.4.3) 30" Apple Cinema Display

Layer Mask/Alpha Channel. Visual bug when moving or transforming

Open test file.
Add solid color Adjustment Layer.
Paint a big "X" on its Layer Mask.
Option(alt)+click on the mask icon to see its Alpha Channel.
Now select Move tool and move mask around.
Alpha channel does not display properly when moved or transformed.

Right Jeanne, should have realized.
A good workaround for this, if you want to see the mask as you move or transform, is to just hit the backslash key to see the rubylith of the alpha channel. That displays correctly.
CB

Alpha channel not be interpreted in FCP 7

Dropping in a .motn file into FCP 7's timeline - the alpha channel is not being recognized. If you render out a file and bring into FCP 7, then the alpha is recognized. Anyone else experience this?

You may need to right/ctrl-click on the .motn file in FCP and tell it to interpret the Alpha channel... (or it might be clicking on it and going under the Clip menu and setting the alpha channel)...
Patrick

Better Alpha channel handling

I've asked for this a lot: alpha channel saving with PS is terrible, and could use an update. And today, I was embarrassed by a bug that caused our game engine to perform poorly as a result of the way Photoshop handles the alpha channel.
The bug: make a 1024x1024 canvas, give it an opaque alpha channel (100% white, every pixel), then Image Size it down to something smaller, like 128x128. Now look at your alpha channel: grey pixels all along the border. ARRGGGHHH!!!1!1! It interpolated, I'm sure, using black alpha outside the canvas that doesn't actually exist, changing, in a powerful, fundamental way, the nature of the alpha channel. Video cards care about this stuff: 99.9% opaque is not 100% opaque. This is terrible.
The request: That PS intelligently offer better defaults when saving an image with an alpha. Right now, it offers, "What was the last bit depth you saved an image to?" Regardless of the fact that the previous image may have no relationship to the following image being saved, the default offering is always "what I did last time". This enables very easy pruning of alpha channels that should be there, or adding opaque alpha channels that shouldn't be there, bloating the file size.
I'd like PS to determine if an alpha channel is present, and base its default choice on that. If one is present, default to 32-bits. If an alpha channel si not present, default to 24-bits. That easy.
If multiple alpha channels are present, I'd like a dropdown menu to pick which one I want. Right now, if you save a PSD with multiple alpha channels to a 32-bit TGA, it throws all alpha channels away, and saves the image with a solidly opaque alpha channel, the choice no one asked for.
For texture work, or works where the graphics card is the destination, not the printed page, this cavalier handling of alpha channels is definitely not sustainable.
I'd love to never have to ask for this again.

Generally speaking the resize of an image on a layer in which the canvas is exactly the size of the data will result in transparency peeking in around the edge (i.e., I'm agreeing with you here, just using Photoshop terms). I've always thought this was kind of poorly thought-out too. As you say, the algorithm must default to using 0 vs., say, replicating (or "clamping") to the alpha of the pixels right on the edge.
I suppose theoretically, the thinking is that if you were to EXPAND the canvas, the area around the image would be transparent anyway, and a subsequent resampling would then have the same result as the above.
Knowing this, one way to work around the problem would be to create a slightly larger image, then Canvas Size it down to your intended resolution. That way there's layer data beyond the edges with which the resizing algorithm can work. I realize that's probably not a practical solution in general, but a trick to keep up your sleeve if you really do need that 128 x 128 image with alpha solid to the edge.
-Noel

Problem with Alpha Channel

The top level track on my project contains an alpha channel. However, being the top level track the tracks below it are invisible.
I have read the "Compositing, alpha channels, and adjusting clip opacity" page. It tells me that I "can choose how to interpret the alpha channel in a file in the Interpret Footage dialog box. Choose Invert Alpha Channel to swap areas of opacity with areas of transparency, or choose Ignore Alpha Channel to not use the alpha channel information at all."
However, when I do this (ie. inverse the alpha channel in the asset) I get the following before and after results:
Summary of goal: I want to adjust the transparency of the top track so that the lower tracks appear.
Help.

If you want to adjust the transparency of a clip, you modify its Opacity property.
Changing the alpha channel properties in the Interpret Footage settings is for when the alpha channel of an asset is not being interpreted/used correctly by the application.

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.

Cannot save alpha channel as PNG. need help.

Hi, I am running PS CS5. I am working on my business logo and love the way it has turned out with a texture I added as a new channel (alpha channel). I am using a transparent background on my image, the only compatible way to save is PNG format.(and this is the only way to go with my website restrictions) So when I go to save as a PNG it isnt saving the new channel I have made. Is there any way around this? Any suggestions would be very helpful. I worked all day on this logo only to find that I cant save it the way I like it. frustrating..................
Linz

Ok, maybe this will help matters. In the beginning I did a google search on how to get the "distressed" look on my logo, this is the link I found, I did all that he said and did acquire the look I want, now I am having trouble saving as a PNG. When I choose to save as a PNG the alpha channel does not save (when I open the saved PNG file the alpha channel is unchecked). I dont know a whole lot about PS, I am new and dont understand alot of the lingo that alot of you are using, but maybe if you see the steps I took on this link then possibly someone may be able to help me. Thanks
http://www.promotinggroup.com/design-tips/distressed-effect-photoshop/

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.

Cover Flow does alpha channels -- almost!

Just for fun, inspired by the semi-transparent musical note default cover art, I tried adding some artwork (PICT with alpha channel) for some albums. It works! For example (one I think most people would recognize, even if it dates me somewhat): Pink Floyd's Dark Side of the Moon cover. I knocked out all the black in Photoshop with an alpha channel, saved and added the pict.
Now when you scroll through, you see only the prism and light beams floating in mid-air; when it's the next or previous album, you see "through" it to the one below it; when it's the current album, it's against black anyway, so it looks correct.
But... disappointingly, I closed iTunes and reopened it, and drat! The alpha channel is not reloaded! It is in fact still there, which I proved by opening the album, info dialog, select artwork, past into Preview (New from Clipboard) and there it is. (For some reason, I could not get it directly back into Photoshop with the alpha channel, but by saving from Preview, it can then be reloaded.)
So, we're left with a tantalizing future feature for Cover Flow! Round, or other arbitrary shapes. Maybe 3-D objects somewhere down the line?
Dual 2Ghz G5 Mac OS X (10.4.7)

Using the sort field to try to force things together doesn't quite work, and certainly not when the album artist has more than one album with guests. I think you'll also find there are some enumeration issues in the album menu which may cause the wrong cover to be displayed as you progress through the library. See my recent post on Grouping Tracks Into Albums for a somewhat long, but hopefully comprehensive, exposition of the issues.
tt2

Clipping Path vs Alpha Channel

Not sure if this is the right place to ask, but wondering which is better for outlined images (no soft transitions, just hard outline.)
I've used both and don't see an advantage to either EXCEPT when converting an InDesign file to PDF. Files with PSDs with clipping paths seem to make much larger pdfs than same file using PSD with alpha channel. Not important for a final press file, but when I have to email screen proofs, then it's a big deal.
Anyone care to weigh in? Thanks.
Ringo

Hi, there,
I found this discussion during a search for alpha channels vs. clipping paths for clipping (for a job I'm working on), and thought I'd offer my own feedback based on my own experiences w/ similar files. I can't really offer a printer perspective, however, although we do work closely with many and also print film fairly regularly for local printers who are not yet Direct-To-Plate.
For what it's worth, I use paths, myself, and save the file as a TIFF. Then I use the Object: Clipping Path menu in InDesign to select the path (I don't specifically designate a path as an actual clipping path in Photoshop anymore, as sometimes an image will have more than one path to isolate different elements).
I find that alpha channels don't look very good when used in InDesign. They're just not that smooth/precise, in my admittedly limited use.
I've uploaded a quick sample to http://i486.photobucket.com/albums/rr222/Xiebinrui/Alpha_vs_Clipping.jpg -- it's pretty self-explanatory, but the left side shows the bottom of an image using an alpha channel created from the original clipping path (cmd-click on the path to create a selection and then click the "create channel" button in the Channels tab, which automatically creates an "Alpha 1" channel), with the original clipped version on the right. I've tried adjusting the threshold and tolerance in InDesign, but it just always looks bad.
I also haven't used the behemoth Photoshop EPS format since my QuarkXPress/Mac OS 9 days (even then, it eventually became possible to use TIFFs w/ clipping paths -- I could finally see my photo correctly instead of with the horrible Quark EPS preview).
Anyway, re: alpha channels, maybe it's just that I don't know the right way to use them, but they don't seem to be very smooth when importing into InDesign (I was working on a job yesterday and today for which I had to download hi-res images from the client -- many of which used alpha channels instead of actual paths, but they're used on white backgrounds in InDesign, so I just didn't use the channels).
So, anyway, I personally use and recommend paths (vector masks, as Artdirectorringo mentioned, seem to work fine, too) as opposed to standard pixel-based alpha channels, in general, if you're going to be placing the file into InDesign.

Alpha channel when not premultiplied

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