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"logging" images

I'm writing a scientific program that has some intermediate results (plots and images) that I'd like to log (additional to the usual text messages).
I like python's logging interface a lot, so I'm wondering if there is a possibility to use it to create log files that include images.
The first idea that came to my mind was creating a log file as a SVG, so the log text is machine readable and the images can be included easily.
Is there a better approach to make this possible?

You could use SVG, but I'm not sure how compact the SVG would be since it would probably (in general) store the bitmap rather than vector information. An alternative would be to base64-encode the image and store it using a structured format, as documented here - the linked example uses JSON, which might be handy to e.g. store metadata about the image, but you could use a simpler scheme if all you're storing is the image and the format is always the same.

Creating Segments in Video

I'm using Python 2.7, PyGTK 2.24, and PyGST (Gstreamer).
To ensure smooth playback from one clip to another (without a blink), I combined all the clips I needed into one larger video. This lets me seek to the exact place I need in code. One of the clips is like a "fill-in", which should loop whenever one of the other clips is not playing.
However, to make my code easier and more streamlined, I want to use segments to define the various clips within the larger video. Then, at the end of each segment (I know there is a segment end event), I seek to the fill-in clip. When I need another clip, I just seek to that segment.
My question is, how exactly do I create these segments? I'm guessing that would be the event_new_new_segment(), but I am not sure. Can I create multiple clips to seek with using this function? Is there another I should use. Are there any gotchas to this method of seeking in my video that I should be aware of?
Second, how do I seek to that segement?
Thank you!

Looks like only GstElement's can generate NEWSEGMENT events, you can't simply attach it to an existing element. The closest thing you could do if not using Python, would be creating a single shot or periodic GstClockID or and use gst_clock_id_wait_async until the clock time hit. But the problem is, GstClockID is not wrapped in PyGst.
I think I'm actually working on some similar problem. Some kind of solution I'm using now, is gluing video streams in real time with gnonlin. The good side: seems to work, didn't have time to thoroughly test it yet. Bad side: poorly documented and buggy. These sources from the flumotion project (and the comments inside!) were very, very helpful to me for understanding how to make the whole thing work.

text layout recognition with python

I'm trying to sort through several thousand scanned files and sort them into folders based on type (ie: if one of the files is a scanned copy of formA, then it should go in the formA folder, if it's a scanned copy of formB, then it should go in the formB folder, etc...). I feel like the best way to match the files and types is based on their text outlines, but am totally new to image processing, so if there's a better solution, then I'm all ears.
I'm working in python. Any ideas of a best way to do this? PIL? OpenCV? imageMagick?
Thanks in advance...

This library is probably of interest to you -
http://code.google.com/p/ocropus/
Its made by googlers and lets you do OCR and layout analysis from python.
I had some trouble installing it, but that was quite a while back, so things may have gotten fixed by now.

I don't know in what format you've got the scanned documents, but pdfminer can do layout analysis for pdf. I guess it would fit the bill for your purpose, provided you get the documents in somewhat decent pdf format (if you've just got "pure images", it won't do you any good)

Getting pixel data from a PythonMagick image?

Does anyone know a way get the pixel data from a PythonMagick.Image instance without having to write it to disk first?
For instance, I can read in an image using:
import PythonMagick
im = PythonMagick.Image('image.jp2')
I would now like to be able to get the uncompressed image data so that I can use it in something else like NumPy or matplotlib, but I can't seem to find any way to do this. I would just use matplotlib or PIL directly but the image format I'm reading in is JPEG 2000 which is only supported by PythonMagick as far as I know.
Any suggestions?

Disclaimer: I don't have PythonMagick built where I am right now and am no expert, so (1) any or all of the following may be wrong, (2) it will certainly be less specific than you'd like, and (3) if someone else knows better I hope they won't be put off by seeing an answer already here. Anyway:
From a quick look at the code, it looks as if you can read pixel values one by one using the pixelColor method on the Image class. This returns a PythonMagick.Color value, from which you can extract R,G,B components. The underlying C++ library supports reading out lots of pixels at a time using Image::writePixels, which is also present in PythonMagick.Image; but I think the proper use of that method depends on other things that aren't implemented in PythonMagick. That's a pity, because I bet it would have been much much more efficient than reading one pixel at a time.
Alternatively and probably better, it looks as if you can write the contents of the image to a PythonMagick.Blob object in memory, which basically does the same as writing to a file only without the file :-). You can choose what format it should write in, just as you do when writing to a file. There seems to be something called get_blob_data for extracting the contents of a Blob. Something like this:
im = PythonMagick.Image('image.jp2')
blob = PythonMagick.Blob()
im.write(blob, "png")
data = PythonMagick.get_blob_data(blob)
The resulting data is, I think, a Python string whose bytes are the binary representation of the image. (I'm assuming you're using Python 2.x, where the string type is 8-bit. I don't know whether PythonMagick works with 3.x.) I think there are some formats that are basically raw pixel data; try "RGB". You can then extract the contents via lots of struct.unpack or whatever.

Recommendations for a simple 2D graphics python library that can output to screen and pdf?

I'm looking for an easy-to-use graphics lib for python that can output to screen as well as pdf. So, I would use code to draw some stuff (simple prims like ovals, rectangles, lines and points) to screen and then when things look good, have it output to pdf.

If you use Tkinter, you can draw on a Canvas widget, then use its .postscript method to save the contents as a PostScript file, which you can convert to PDF using ps2pdf.
postscript(self, cnf={}, **kw)
Print the contents of the canvas to a postscript
file. Valid options: colormap, colormode, file, fontmap,
height, pageanchor, pageheight, pagewidth, pagex, pagey,
rotate, witdh, x, y.

Matplotlib should be able to do it. See event handling here: http://matplotlib.sourceforge.net/examples/event_handling/index.html

You can use the Python Imaging Library for drawing images which can easily be displayed in various UIs, e.g. by displaying a jpg. Then, use ReportLab. Here's an example which shows how to use ReportLab with an image.
I'm not sure what you mean by drawing to "screen", i.e. if you're working with a specific UI toolkit. But if it's acceptable to draw and display PDFs without using an intermediate image (jpg, etc), then you might consider the PyX library, which makes it quite simple to do graphics with PDFs.

You could look into matplotlib, which is mainly for plotting but you could probably do some basic drawing.
Then there is pygame. But I'm not so sure if it can generate a pdf, however you can do 2D graphics with it.
There is something called ReportLab that can generate pdf's. Here is a bunch of tutorials using it.

This is a tricky question, because there are so many libraries available - there is a trade-off between beauty/easiness.
What I've done and works great is to produce the Postscript directly, it is not difficult at all, and you can preview it using Ghostview; converting tyo PDF is trivial (ps2pdf). Learning how to tell Postscript to create lines and circles is extremely simple.
If you want more extensibility, then go to Matplotlib, but beware of the many times when it will "decide for you what looks best" even if you don't like it.
Good luck.

Creating PDFs is always a pain, it doesn't make sense if you do not aim to lose sanity.
With that said, you are aiming to do two completely different things: when you draw to screen you draw into a raster bitmap, while PDFs are mostly dynamic, like HTML. (unlike HTML they are more prone to be the same over different platforms, but that's beside the point)
If you really want to do that, the solution might be finding something that outputs PDFs, and then showing the generated PDF on screen at every step.
I guess that's the only way to have WYSIWYG results.