[Image-SIG] adding overlay & text to many files
pander at users.sourceforge.net
Thu Jan 29 17:53:00 CET 2009
Here is a way to add text, see attachment. I've extended the test cases
with capitols with diacritics. On the list a question regarding this
arose, so it was good to double check this.
If possible, I would like to have this module included into PIL. Once I
had it revied, but would like to resubmit it again since the PIL list
has become more active again, especially regarding text overlays.
> Op woensdag 14-01-2009 om 19:42 uur [tijdzone -0800], schreef Bernard
>>> Phatch has already a text action which has done the hard work already as
>>> well. Just start from that as a base and hack it to use a csv file as
>>> input instead of a fixed text. If you have played with python and PIL
>>> already, it should be not that hard.
>> Thanks for the help.
>> I've taken a look at the tutorial and the existing text.py action.
>> I am new to Python, and have never used PIL, but it does look do-able..
>> A couple of questions on the existing text action:
>> 1) Is the the "cache" dict the only recommended way to maintain state between invocations?
>> 2) What is the "values" method of the Action class in the text.py file?
> The values method convert relative values (given by the user) into
> absolute values based on image properties (height, width, ...). For
> example for a pixel value a user can enter absolute pixels, metrics (cm,
> mm, ...) or a percentage. In the end we need absolute pixels to work
> with PIL. So metrics are converted to pixels by multiplying with the
> dpi. Percentage are calculated by multiplying with the appropriate image
> property. For example for a horizontal offset of 5%, we take 5% of the
> image width. The font size is based on the average of the image height
> and width.
>> 3) What does the "global" statement in the init() method do, and why is it there?
> Phatch uses a very simple plugin mechanism. It imports all the actions
> at startup. In order not to load modules which might not be used and to
> keep one action limited to one file, we need a lazy import for modules
> which are only necessary when executing the action. Therefore they are
> grouped in an init method and global is used to make them globally
>> 4) What is line 38 trying to do, and why is it in the if clause?
> If no (truetype) font is given, Phatch will use the default PIL font
> which AFAIK can not handle unicode (e.g. chinese characters). Therefore
> text needs to be converted to ascii. Phatch choses to replace a
> character with a ? if it can't be encoded.
>> Also, was this file based on the Watermark code? Many if the code comments would indicate so.
> Indeed. Many actions are based on other ones. This is the fastest way to
> write new actions.
>> (Running out of Ubuntu Intrepid repo)
> If you start developing, please checkout phatch from the bazaar
> repository (bzr lp:phatch)
>> Where can I find further docs on the plug-in / action API?
> I guess you've read already:
> The best is to study and understand the source of the other actions and
> see them in action.
>> Thank you
> You're welcome!
> Image-SIG maillist - Image-SIG at python.org
-------------- next part --------------
A non-text attachment was scrubbed...
Size: 15370 bytes
Desc: not available
More information about the Image-SIG