[Qgis-developer] working with temporal data

[Václav Řehák]

2010/8/3 Martin Dobias <wonder.sk at gmail.com>:
> Hi Anita
>
> On Sun, Aug 1, 2010 at 12:48 PM, Anita Graser <anitagraser at gmx.at> wrote:
>> Hi,
>>
>> Few days ago, I stumbled upon this new ESRI tool to work with temporal data:
>> http://blogs.esri.com/Dev/blogs/arcgis/archive/2010/04/16/New-experience-and-tools-for-working-with-temporal-data.aspx
>>
>> Such a tool would be really useful for my work any many others too I
>> believe. So, I've been thinking about writing a python plugin that basically
>> adjusts the layers subsetString to the chosen time frame. But before I start
>> coding, I'd like to ask your opinion on what would be the best way to
>> implement such a functionality and maybe somebody already implemented it or
>> something similar.
>>
>> On a related topic: I'd also be interested in a "Save as Animation"
>> functionality similar to "Save as Image". Do you think it's reasonable to
>> implement such a functionality in Python? Do you know any libraries worth
>> considering for this job?
>
> An interesting idea for a plugin! The proposed approach with
> subsetString should work. When it comes to handling of animations, you
> could try to use mencoder (a companion of mplayer) for converting a
> series of images to video [1]. I have also some experience with ffmpeg
> library for encoding video - it has C api, but it looks there are some
> python libraries that wrap it (pyffmpeg, pymedia).
>
> [1] http://www.mplayerhq.hu/DOCS/HTML/en/menc-feat-enc-images.html

I also find this functionality very appealing for a plugin - it would
help a lot for a home range study we do using QGIS. Talking about
temporal data, is there any reason why there is no support for
datetime attributes in QGIS, only numbers and strings? In our study we
need to create point features for locations where an animal was
observed and the filter those features based on date and time.

Vaclav