User’s Manual v.15
QVidium
®
H.264 HD Video Codecs
™
Copyright 2011-2014 QVidium
®
Technologies, Inc.
Page 48 of 71
10
Encoding & Decoding to/from Files
The QVPRO, QVENC, and QVDEC each have two USB interfaces that allow you to connect a
USB Flash stick or an external disk drive. You can encode a video stream directly to a file on this
storage device with the QVPRO or QVENC, and you can also play back a saved file from this
external storage device with a QVPRO or QVDEC. You can access external storage via either the
web interface or a command-line interface. You can access external storage via the command-line
interface in one of 3 ways: 1) through the RS-232 Console port (115.2 KBaud, 8-N-1, No Flow
Control, Null Modem cable), 2) Telnet (port 23), or 3) SSH (port 22). For
telnet
or
ssh
, log in
using username
root.
The initial password is
root
, but you can change this from the web GUI
using the System/Password menu.
10.1 Web Interface
10.1.1 Recording: Encoding to a File
You can configure an encoder profile to record to a mounted USB external storage device, such as
a USB Flash stick or disk drive. However, this attached storage must be formatted with a
Microsoft-compatible format, such as FAT, FAT32, or NTFS. (You must use the command-line
interface, described below, for Linux-compatible memory formats.) Simply plugging in the memory
device will cause it to be automatically mounted. To be certain that the USB device is properly
mounted and to see how much capacity is available for recording, just click on Usage in the USB
menu (see below). You should wait a few seconds after plugging in the USB device before clicking
on Status or starting the encoder to record a file in order to give the system time to mount the
device.
As we describe in Section 2.2, your choices for output device are Network, ASI, File TS, or File
MP4. Selecting File TS or File MP4 will record the encoder output to a file on a mounted USB
storage device. File TS will save the encoded stream as an MPEG Transport Stream (typically
given a “.ts” file suffix). File MP4 will save the encoded stream in Apple QuickTime format.
Broadcasters typically store their video content in Transport Stream format. Alternatively, MP4, or
QuickTime file format
(typically given an “.mp4” file suffix), is used be Apple for iTunes video
content. However for MP4, the encoder can only encode as Baseline MPEG4-AVC format.
Starting the encoder will cause the output to continuously stream into the storage device until you
either manually stop the encoder, or the device fill to capacity. However, we would caution you
against allowing the external device to fill to capacity, as this could cause problems with the
recorded content. You can calculate how much recording time (in seconds) your storage device
contains by multiplying the number of available bytes of storage your device contains by 8 to
convert to bits of storage capacity, and dividing the resulting product by the total bitrate, calculated
as the sum of the video bitrate and the audio bitrate times 1.02 to account for a 2% TS stream
overhead. Dividing this number by 3,600 give you the number of hours you can record.
10.1.2 Playback: The File Menu Interface
Once you have content recorded on a mounted memory device, playing out video clips is simple,
and accomplished through the
File
menu interface. Available commands are:
File
, to list, and
optionally delete, the files in the memory;
Usage
, to show how much of the memory has been used
and how much is still available;
Play
, to bring up the interface to play a video clip,
Status
, to show
the current status of the play-back (this is the same as Decoder Status);
Show Log
, to show the
log file in case of problems; and
Stop Play
, to stop play back of a video clip. Figure 7, below,
shows and example of the
Files
,
Usage
, and
Play
menus. The
Files
menu lists all the files on the
