They are meant for efficiently and safely transferring data to decoder methods of classes rawdec, vt, dvb_mux, and the analog de-multiplexer classes idl_demux, pfc_demux and xds_demux. These are transparent pointers to C structures, and thus not directly accesible from Perl (although there is function Video::ZVBI::get_sliced_line(), which allows unpacking a VbiSlicedBufferPtr). The pull variety of capture methods produce blessed references of types VbiRawBufferPtr and VbiSlicedBufferPtr for raw VBI samples and sliced VBI lines respectively. Blessed references VbiRawBufferPtr and VbiSlicedBufferPtr For analog television transmission this involves capturing selected lines within the Vertical Blanking Interval (VBI) and "demodulating" the digitized wave form to raw data. For digital television transmissions (DVB) this mostly involves demultiplexing of the data service sub-stream from the overall transmission stream.
This class allows receiving data through a video device. The following is an overview how functionality provided by libzvbi is structured into classes, and how the classes are connected: Class "Video::ZVBI::capture" Check for yourself which one fits your needs better. Hence when additional details are needed, it's recommended to look at libzvbi documentation, or directly at its source code.įinally note there's also another, older, module which covers VBI data capture: Video::Capture::VBI and based on that another one which covers Teletext caching: Video::TeletextDB.
#Teletext net 5 manual#
Note: This manual page does not reproduce the full documentation provided by libzvbi by means of doxygen: While method and parameter descriptions are fully included, some data structures may not be not fully documented here. Most of the functions and parameters are exposed nearly identical, or with minor adaptions for the Perl idiom. The ZVBI Perl module covers all exported libzvbi functions. The library was written for the Zapping TV viewer and Zapzilla Teletext browser."
#Teletext net 5 driver#
Official library description: "The ZVBI library provides routines to access raw VBI sampling devices (currently the Linux V4L & V4L2 APIs and the FreeBSD, OpenBSD, NetBSD and BSDi bktr driver API are supported), a versatile raw VBI bit slicer, decoders for various data services and basic search, render and export functions for text pages. The ZVBI library allows to access broadcast data services such as teletext or closed caption via analog video or DVB capture devices.
This module provides a Perl interface to libzvbi. Video::ZVBI - VBI decoding (teletext, closed caption.
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