Input/Output Formats¶
Input¶
Flowty uses the OpenCV VideoCapture API to load videos. It defaults to the FFmpeg backend.
Flowty is built to support reading from:
- H263
- H264
- VP9
- JPEG
For any of the video formats you can simply provide /path/to/video.ext
as
the src
argument. To use a folder of sequentially numbered JPEGs as input
you have to provide an image filename template such as
/path/to/video_dir/frame_%06d.jpg
(like specified in the VideoCapture
constructor docs).
Output¶
Currently only one output format is supported: splitting flow into u, v pairs,
quantising them and storing them as JPEGs. The dest
argument must be a python
format template
with two interpolations: {axis}
and {index}
.
{axis}
will be replaced withu
orv
depending upon the direction of the flow field being written.{index}
will be replaced by the flow frame index being written, typically you’ll want to add some format specifiers to this to 0 pad it, e.g.{index:06d}
.
An example template dest
string is /data/flow/{axis}/frame_{index:06d}.jpg
.