I would like to create a list of all available pixel formats for OpenGL. On Windows, I can do this by calling DescribePixelFormat in a loop, increasing the pixel format id, until it returns false.
Unfortunately, it seems that aglDescribePixelFormat does not work like this. Its AGLPixelFormat parameter is a pointer to an opaque struct - I can't call this in a loop.
Apple's documentation doesn't provide any hints either, nor does google. Any AGL experts out there willing to share their knowledge?
Edit: I've seen mention of a aglListPixelFmts() function but this is not listed in agl.h, nor can I find any mention in Apple's documentation. What gives?
Actually, Apple's documentation does give a hint. Under aglDescribePixelFormat, it says:
To retrieve the data in pixel format
objects other than the first one in
the list, call aglNextPixelFormat.
Then pass the returned pixel format
object to aglDescribePixelFormat to
retrieve an attribute value.
Related
When using the Windows-Machine-Learning library, the input and output to the onnx models is often either TensorFloat or ImageFeatureValue format.
My question: What is the difference between these? It seems like I am able to change the form of the input in the automatically created model.cs file after onnx import (for body pose detection) from TensorFloat to ImageFeatureValue and the code still runs. This makes it e.g. easier to work with videoframes, since I can then create my input via ImageFeatureValue.CreateFromVideoFrame(frame).
Is there a reason why this might lead to problems and what are the differences between these when using videoframes as input, I don't see it from the documentation? Or why does the model.cs script create a TensorFloat instead of an ImageFeatureValue in the first place anyway if the input is a videoframe?
Found the answer here.
If Windows ML does not support your model's color format or pixel range, then you can implement conversions and tensorization. You'll create an NCHW four-dimensional tensor for 32-bit floats for your input value. See the Custom Tensorization Sample for an example of how to do this.
I want to write audio data that follows the correct subformat of a WAVEFORMATEXTENSIBLE object. Microsoft provides a list near the bottom of this article:
https://learn.microsoft.com/en-us/windows-hardware/drivers/ddi/ksmedia/ns-ksmedia-waveformatextensible
I can not find documentation on the subtypes. If I find KSDATAFORMAT_SUBTYPE_IEEE_FLOAT, what are the ranges of the floats?
KSDATAFORMAT_SUBTYPE_DRM? How do I deal with the drm?
KSDATAFORMAT_SUBTYPE_ALAW? What is ALAW even?
I have an XML file produced with Gnumeric that contains images, stored as GOPixbuf strings inside XML. They look like this:
eXyA/4KEiP9xcnf/f3+E/3l5ff9xb3L/jo2Q/29wdP+ [truncated]
For each string I have width and height, and a rowstride parameter, like in this example:
<GOImage name="Image(70)" type="GOPixbuf" width="151" height="135" rowstride="604">
Is there a reasonable way to convert that to an image - any format will do?
I'm conversant with perl and image conversion tools (imagemagick, gimp) but I have not found any documentation by googling beyond GTK or GOffice docs.
You have already found stuff that is helpful. But since there are no Perl bindings for this on CPAN, you would have to make your own if you want to use Perl.
Fortunately, you don't have to know XS to do that. You can use FFI::Platypus to create temporary bindings and only map what you need.
The docs you have probably already found have a Getting started with GOffice section. After a quick check I found that on my recent Ubuntu there is a package that contains that lib. It is called libgoffice-0.10-dev.
Now you can set that up and play around with the lib functions. Somewhere in https://developer.gnome.org/goffice/unstable/GOImage.html there probably is a method to read and convert it.
One of the good ones might be go-image-get-pixbuf, which returns a GdkPixbuf. That in turn has a very extensive documentation. Maybe what you need might be in this one.
Good luck.
Is there a data structure within LiveCode that can be used as a "holder" for associated data, letting me handle it collectively? I come from a Java / Javascript / C background so I am looking for a Class or Struct sort of data structure.
I've found examples of Groups, which seem to have some of this functionality, but it feels a bit like I'm bending the language to meet my needs.
As a specific example, suppose I had an image field on my screen that would randomly display an image and, when pressed, play an associated sound clip. I'd expect to create a list of "structures" that contained the path to the image and the path to the associated sound clip, and use that data to populate the image field and to decide what sound clip to play.
Would a Group be the correct structure to use in this case? Or am I approaching this in a way that isn't really fitting with the way LiveCode works?
It takes a little getting used to, but the xTalk world is much simpler and more open than any ordinary procedural language. So much of what you once had to manage is no longer required.
So when splash21 said that you could store all your image and sound references in a custom property, he was really saying that the LiveCode environment contains intrinsic, high level functionality that makes these sorts of things instantly accessible, and the only thing required of you is to call for them, and they simply work.
The only way to appreciate this is to make a few simple programs, to really see what is possible. Make your application. Everything you mentioned can be accomplished with perhaps a dozen lines of code in a single handler. I recommend that you join the LiveCode use list and forums. The community is vibrant and eager to help, frequently with full blown solutions to specific problems, but more importantly, as guides and mentors to new users
Craig Newman
Arrays in LiveCode are actually associative arrays (like hash maps). A key is associated with a value. The value might be as well an array.
Chapter 5.5.7 of the User's Guide says
Array elements may contain nested or sub-elements, making them multi-dimensional.
This type of array is ideal for processing hierarchical data structures such as trees or
XML. To access a sub-element, simply declare it using an additional set of square
brackets.
put "ABC" into myVariable["myKeyName"][“aChildElement”]
see also
How to store pictures in a stack?
Dave- I'm hoping to get a struct-like container implemented in the near future. Meanwhile you can, as splash21 mentioned, use custom properties (or better yet, custom property sets) to do what you want. This will give you a pseudo-struct for each object and you can implement the file and sound specifications into the properties. And if you use that in conjunction with a behavior object you'll end up very close to a real inheritable class formation.
I'm looking for a way to specify that the images returned by the Google Custom Search API have a square format.
I've tried tbs=iar:s (because I've read Using the Custom Search API (REST JSON) to search for square images), but it doesn't work.
Have you an idea please ?
The problem is that tbs query parameter only applies to a regular image search on Google. For example, if you wanted to search for cat pictures with a square aspect ratio, you could do a search like this:
http://images.google.com/?q=cat&tbs=iar:s
But the Custom Search API uses a completely different set of parameters. The full list of supported parameters is shown in the REST documentation.
Some of the tbs queries do have equivalents. For example:
tbs=ic:gray translates to imgColorType=gray
tbs=isz:m translates to imgSize=medium
tbs=itp:clipart translates to imgType=clipart
But sadly there appears to be no equivalent for the iar aspect ratio filter. I tried guessing a few queries (things like imgAspectRatio=square) in case there was an undocumented parameter, but didn't have any luck with that.
The best alternative I could suggest is using imgSize=icon. This tends to return images that have a square aspect ratio, but with the unfortunate side effect that the images also tend to be rather small (the largest size I've seen returned is 256x256). Depending on your needs though, this may be good enough.
I apologise if this isn't particularly useful to you. I'm not just trying to grab the bounty on this question, so feel free not to vote this answer up. I just wanted to let you know what I had found in case it was of some help.
You can simply use both tbs=isz:l,iar:s that way it will return only large images with same aspect ration.