My application have some problem on opening 32bit BMP images.
some image has alpha channel and with certain value, but window image viewer, picasa photoshop seems ignore the alpha channel.
how can I know whether I should take the alpha channel into account.
So I need a specification of 32bit BMP Image. Can anyone help?
Many thanks!
Also in Wikipedia: BMP
The ultimate documentation for the BMP format comes from the authors of it - Microsoft. Read it at MSDN.
http://www.wotsit.org/ has the answer:
(Warning for popups when visiting following link)
http://www.fortunecity.com/skyscraper/windows/364/bmpffrmt.html
Related
How do I convert Adobe Photoshop points to pixels in CSS?
My font size is 48pt, how does that convert to pixels?
Also, are there tools that help convert photoshop psds into CSS/Html?
You can use points to declare the size of your text in css if you like, there's no need to convert. That way if your photoshop file is set up for 72ppi, you see the same size of font in both photoshop and web.
If you building mobile thou, sizes work differently. Than the best thing is to look for a guide, depending on which devices you're building for.
I believe there isn't a tool to convert photoshop pds into css/html. Although, Zeplin may helps. Zeplin is a tool to easily export assets and make guidelines for projects, but it also helps you create a css file from your screen. https://zeplin.io/ It's really nice!
If your Photoshop document is 72pixels per inch (the standard of the web). 1px = pt.
OSX renders 72 ppi (dpi), windows renders bitmaps at 96 ppi (dpi). Knowing the 72ppi or 96ppi numbers can help you work out what's going on.
Photoshop will alter the Text Point size depending on what the image ppi is set to.
However, with today's high pixel density displays the whole dpi to ppi is something of a fudge. Wikipedia has a good, but dated, article on pixels (screens) vs dots (print)
https://en.wikipedia.org/wiki/Dots_per_inch
I used Word 2007 to create a PDF file with an 1526px * 900px image filling a whole page. This is not the first time it's happened, but Google Docs PDF viewer absolutely mangles the colour rendering making it unusable.
I've taken screenshots at the same zoom level in Google Docs viewer and Foxit Reader.
Here's an image for comparison:
It's awful! I've tried messing about with some things, but can't find anything that can correct this issue.
In Chrome you can select "Print" and then "Save as PDF". The image quality in the saved PDF file will go up significantly, compared to the one from "Download as PDF". Google seems to be optimizing images to preserve bandwidth.
Let it be recorded here, 16 months after the present original posting by Turkeyphant and a similar posting [1] on the Docs+Drive product forum, that the problem appears to have been fixed within about the past week. Since that time, when a pdf (or Word) file is opened that resides on the Docs+Drive cloud, the file is rendered with what appears to be proper 24-bit color. The treatment whereby the color was reduced to 5 bits, which could encode 32 colors or 32 shades of gray or 16 of each, depending on the image, has been abandoned.
To the best of my knowledge the Docs+Drive staff have not announced this change, either on their Blog or on their product forum. I noticed the change a few days ago and noted it on the conversation [1].
[1] (2013-05-21) Problem in pdf-viewer with color images
https://productforums.google.com/d/msg/docs/_bdfiYgjF2s/5PDMdp9MhFQJ
It might have something to do with compression of the image in the PDF.
I mean, PDF supports JPEG2000-encoded images (JPXDecode Filter) and PDF Reference states that:
From a single JPEG2000 data stream, multiple versions of an image may
be decoded. These different versions form progressions along four
degrees of freedom: sampling resolution, color depth, band, and
location. For example, with a resolution progression, a thumbnail
version of the image may be decoded from the data, followed by a
sequence of other versions of the image, each with approximately four
times as many samples (twice the width times twice the height) as the
previous one. The last version is the full-resolution image.
Google Docs viewer might be displaying only first version of the image (with lower resolution or lower color depth) thus producing "awful" output.
Perhaps the attached pair of images will help towards clarifying what is happening with color in images that are rendered through the Google Docs pdf viewer. I inserted the Wikipedia image RGB_Color_Solid_Cube (1024*1024 pixels) into an otherwise empty Google Docs text document, converted it to pdf, and viewed the resulting pdf files two ways: once through the Google Docs+Drive pdf viewer and once through the regular pdf viewer of the Chrome or Firefox browser. Then I made screenshots. Here is the RGB Color Cube via the Docs PDF Viewer and here is the RGB Color Cube via a regular browser PDF Viewer.
The color resolution in the Docs PDF Viewer version is really awful; it looks like 64 colors at most. Maybe someone else is able to recognize this kind of rendering and identify the problem better.
This is related to compression and it's something that you can't change in the default view of Google Docs Viewer. The simple solution is to upload the PDF and just serve it from the site in an iFrame. Here is an example:
Problem Embedding Google Docs PDF Solution
Mike
color settings --> working space
Usability post tells us
at the “Working Spaces” section and select the sRGB IEC61966-2.1 profile
Smashing magazine tells us to
set the working space for RGB to Monitor RGB.
http://viget.com/ also recommends
changing the top drop-down to Monitor Color.
What should we use?
Second part of the question: saving for web:
Should we always uncheck the 'Convert to sRGB'? There is also contradictory tutorials on this one.
Thank you very much in advance!
Web images should be saved whithout any addition data. No color profiles. Many browsers read color profiles of how they are want.
sRGB IEC61966-2.1 or Monitor RGB is the same profile in color settings.
You doesnt need to check convert to rgb. Try to check but you will nothing to see changes if you work in sRGB colors already.
When I am using PDF Creator to create PDF documents the quality of the fonts is not exactly the same as when I am using Adobe Acrobat to create the same PDF. The fonts when creating with pdf creator are a bit more fussy (not as crispy as with Adobe).
Does anyone know if/how I can resolve this?
Here are 2 example documents that demonstrate what I mean:
Example of PDF created with PDF Creator
Example of PDF created with Adobe Acrobat
I don't have a solution for you unfortunately but I can tell you that what you are seeing is anti-aliasing. If anti-aliasing is enabled, fonts at lower resolutions will get that "fuzziness" that some people believe helps with reading. It might not look as pretty but it improves word recognition (so the theory goes). But that's beside the point. What you need to do is look for a setting to disable anti-aliasing. If you can't find it then you might have to look into setting actual Ghostscript settings, possibly dTextAlphaBits but I'm not a Ghostscript expert.
You can tell its anti-aliasing because the "fuzziness" only appears when the fonts are small. Once you zoom in it all goes away.
Image zoomed out:
Image zoomed in
Does anyone know if we can resize a QR-Code easily by using a proper vector program OR, is the size information contained on that code, hence, we will not be able to resize without changing the code ?
Thanks in advance.
You can resize as much as you want. The information is encoded in the pattern of the data, not in the size of the dots themselves. As long as a scanner can resolve properly between light/dark, the QR code should be readable at any size.
Update 2016: If someone happens to need to upscale a QR code image in some sort of browser/webview - you might get away with a simple CSS property:
img {
image-rendering: pixelated;
}
This way the upscaled image stays sharp.
See a comparison here: http://codepen.io/erkkit/pen/GodxGX
For high resolution (vector image) QR code for printing/publishing:
Get your free QR code
Right-click-and-save OR PrintScreen the QR code
Open/insert it in Photoshop, crop the QR code, and save as *.psd file (default Photoshop format)
Open that *.psd file with Adobe Illustrator – and you get the vector QR code. DONE! :)
Don't just re-size it that will make the edges blurry. You want it to have hard edges like MS-paint or the pencil brush in Photoshop. Open the file in Photoshop and go to IMAGE - RE-SIZE IMAGE and make sure Nearest Neighbor is selecting from the bottom drop down menu before you click OK
You CAN'T, not with the free QR generators. Unless you do some Adobe Illustrator tweaks with Live Trace/Paint afterwards. The abundant free QR generators are a joke when it comes to publishing the QR code you need. Resizing an originally low resolution image (the previous comment) for publishing/printing purposes is the most rediculous statement I've seen in a while. The guy doesn't know what he is talking about.