affie/video4linux.jl

Julia interface for video4linux

video4linux.jl's Issues

`init_device(fid)` not working with webcam on `/dev/video0`

Hi,

Just thought I'd list an issue that I am seeing, although I don't have an answer to help fix it just yet. From the README example, I'm trying to read an image from the laptop webcam. The webcam does exist at /dev/video0 and can be read via VLC Capture Device mode just fine. It fails pretty hard though, dropped out of Julia. Using Ubuntu 16.04.

               _
   _       _ _(_)_     |  A fresh approach to technical computing
  (_)     | (_) (_)    |  Documentation: https://docs.julialang.org
   _ _   _| |_  __ _   |  Type "?help" for help.
  | | | | | | |/ _` |  |
  | | |_| | | | (_| |  |  Version 0.6.0 (2017-06-19 13:05 UTC)
 _/ |\__'_|_|_|\__'_|  |  Official http://julialang.org/ release
|__/                   |  x86_64-pc-linux-gnu

julia> using Video4Linux
depfile = joinpath(dirname(@__FILE__()), "../deps/loadpath.jl") = "/home/dehann/.julia/v0.6/Video4Linux/src/../deps/loadpath.jl"

julia> using ImageView

julia> using Colors, ColorTypes

julia> # Warning! no memory and device protection is implemented yet, therefore doing things out of order will cause julia to crash!
       ## set io method to read()
       set_io_method(Int64(0))

julia> ## open device
       fid = open_device("/dev/video0")
17

julia> ## init_device(fd, force_format);

julia> init_device(fid)
Device does not support read i/o
dehann@mrg-galago-01:~$ 

Object files should be compiled localy not kept in repo

Not sure if this was intentional, but compiled object files should probably not be in the repo. The C we can look at compiling the C file with Pkg.build() during the package installation process:

From https://github.com/Affie/Video4Linux.jl
   5273095..e5ee4d7  master     -> origin/master
 * [new branch]      test/expand -> origin/test/expand
Updating 5273095..e5ee4d7
Fast-forward
...
 deps/v4lcapture/src/v4lcapture.o | Bin 15632 -> 0 bytes
...

That said, I'm not seeing that file on my local repo on master (so likely in the git history somewhere). Doesn't really matter if the object file has already been removed.

Move to JuliaRobotics?

Hi,

Is that maybe a good or bad idea?

Memory and device protection measures

There is currently only basic checks to protect/inform julia from/of memory and device errors. To do:

• Basic protection and checks implemented with return value
• Device opening closing errors
• Access wrong memory
• Out of order such as read before initialize