mnhrdt / vpp

simple C library for video processing pipelines

vpp

vpp is a video processing pipeline library.

$ make
$ ./bin/readvid 'yourinput/*.png' - | ./bin/example - - | ./bin/writevid - output/%03d.tif

See src/example.c for an example of a recursive average using vpp.

A pipeline is defined as a sequence of programs communicating using vpp's C functions through unix pipes (or files). A given program can have many inputs and outputs, allowing for complex pipelines.

To load and save a video, readvid and writevid are provided (but can be replaced with your own). They are using iio to load/save sequence of images.

Another example (temporal difference of the 30th first frames):

$ mkfifo copy;
$ readvid 'yourinput/*.png' - \
  | vp take - - 30 \
  | vp dup - - copy \
  | vp skip - - 1 \
  | vp zip - copy - 'x-y' \
  | writevid - test/%04d.tif      

Release notes

• v2.3.2 - 2018/09/17

  • fix an issue with vpp_init_input introduced in v2.2.0
  • improve error reporting
  • vpp_init_input now returns NULL if the frame size is invalid (it should be positive)
    • this might indicate that a writer wrongly initialized its output

• v2.3.1 - 2018/09/16

  • add operator 'vp zip'
  • fix two issues with 'vp dup'

• v2.3.0 - 2018/09/16

  • add function 'vpp_init_inputs' to initialize multiple inputs at once, required for complex pipelines.
  • add two vp operators: dup and buf

• v2.2.0 - 2018/09/15

  • add 'vlambda' (from the code of plambda)
  • move 'vp exec' to 'vexec'
  • fix a bug where the libc kept the header in buffer

• v2.1.0 - 2018/09/13

  • add a 'vp' binary that contains many operators:
    • basic blocks: take, repeat, first, last, skip, concat, timeinterval, average, count, max, min, sum
    • more advanced: map, reduce, scan, framereduce, exec

• v2.0.0 - 2018/09/12

  • removes the notion of video length (breaks API and file format compatibility with v1)

• v1.0.0 - 2018/09/11

  • first working version

TODO list

• documentation for the basic building blocks in src/vp.c

For readvid and writevid:

• support multipage tiff
• support video format