The VideoLAN Forums

An imaging device requires several custom modules in order to stream and view images in the VLC Media Player.

The user base is Win32/64 systems running WinXP -> Win7.

A cross-compiler to build win32 applications has been setup using Virtual Box/Ubuntu.

Modules:

Access: A serial stream available through a win32 driver provides the camera input.

Demux: The data stream from the recorder may consist of the several camera views

Decoder: A custom decompression scheme is used.

Cross-Compile of Modules:

Does any have experience building an OutOFTree Module using a cross-compuler enviroment for win32/64.
According to the instructions in the OutOfTreeCompile wiki, the pkg-config environment
variables need to be changed. (Where do you do this?)

Access Module:

Is it possible to pull data from a serial line and use it within an Access Module

The access module can get its data from pretty much anything, as long as it is a byte stream. A serial line is a byte stream. But if it were not a byte stream, you'd need to combine the access and demux module in one "access_demux" module instead.

Are there some examples of an access module accessing a flash drive.

How does the access module request more data from the input device. Is it possible to set-up bi-direction communication
with the input device using the access module? The access module will need some way of requesting more data from
the input device.

Are there some examples of an access module accessing a flash drive.

Uh? Usually flash drive are mounted as a file system and accessed with normal file system functions (modules/access/file.c).

How does the access module request more data from the input device.

Access module needs to define either pf_read or pf_block function to provide data.

Is it possible to set-up bi-direction communication with the input device using the access module?

You can do whatever you want as long as it is code. A module is just a glorified set of callbacks to represent a byte stream, optionally with seek capability.

The access module will need some way of requesting more data from the input device.

Uh? Usually flash drive are mounted as a file system and accessed with normal file system functions (modules/access/file.c).

Sorry I forgot to detail the question.

The data on the flash drives will be stored in a custom filesystem which is not FAT or FAT32. Data must be read from the drives using RAW byte reads rather than using the standard filesystem calls: fopen(), fread(), ... fclose().

On a Windows OS, this can be accomplished by using ADMINISTRATOR-level access to call device-driver commands to scan for known intefaces: eg. DIGCF_INTERFACEDEVICE, attempting to open and establish a handle to them if found, then proceed with RAW-LEVEL reads.

Can Window-specific header files such as <winioctl.h> be used in a module when cross-compiling vlc?

In the Building section of the OutOfTreeCompile page, the last sentence states:

If cross-compiling, you will probably need to adjust the pkg-config environment variables. Otherwise pkg-config will use the native VLC development files (if found) or simply fail.

For example, if cross-compiling i686-w64-mingw32 for Windows 32-bits, using the Mingw-w64 toolchain, do
these variables need to be set?
Are there other variables pkg-config environment variables requiring adjustment?

Access module needs to define either pf_read or pf_block function to provide data.

Is it possible to call to a win32 dll from a function? The drivers for the serial-like communications
are stored in the DLL. The header file is also available.