AV-Sync media preparation (Classic)

This page helps you prepare the two files that AV-Sync on Podcatcher Classic needs, both made from your original video:

File	What it is	Where it goes
Video file	Your video with the sound replaced by the AV-Sync track	The media player
Audio file	The original sound as MP3	The AV-Sync Stop in the Tour Editor on the Platform

The AV-Sync Video Tool makes both files for you. You can also make them by hand.

With the AV-Sync Video Tool

1. Download the AV-Sync Video Tool 0.4 (Windows .exe).
2. Open it. If Windows shows “Windows protected your PC”, choose Run anyway.
3. Drag and drop your video onto the tool, or open it from the tool.

The tool writes two new files next to your original:

• <filename>_video.mp4 — put this on the media player.
• <filename>_audio.mp3 — upload this to the AV-Sync Stop in the Tour Editor.

Without Advanced ticked, the tool uses settings that suit most cases.

Advanced video settings

Setting	What it does
Convert	Transcodes the video to H.264. Unticked, the video goes into the output file unchanged, with the same resolution and quality. The tool turns this on by itself if your codec is not supported in MP4 — the progress then shows “Converting video”.
Flexcode	Lets you enter the IDentifier code for flexible mode (A1:00 to A1:FF). See AV-Sync for Podcatcher Classic.
Room audio	Unticked, the video only carries the AV-Sync track. Ticked, the output has a stereo track with the AV-Sync track on the right and the original sound (mono) on the left, so you can also play the sound in the room.

Advanced audio settings

Setting	What it does
Bitrate	Bitrate of the audio for the Podcatcher Classic. Higher means better quality but longer sync times. Recommended: 64k for mono, 128k for stereo. On auto, the tool picks a bitrate based on your file.
Channels	Reduce stereo to mono to lower the bitrate and the sync time per device. Stereo is advised when visitors use headphones.
Extend	Adds silence to the end of the audio. Use it for loop correction when the media player and the Podcatcher Classic both restart the video automatically.

By hand

You need video editing software. The examples below use Avidemux and Audacity; any comparable software works.

1. Make the audio file for the Podcatcher Classic

1. Save the original video somewhere easy to find.
2. In Avidemux, open the video, choose Audio → Save audio and save it, for example as MyAVSyncClip.m4a.
3. In Audacity, open that file. Make sure Project Rate (bottom left) is 48000 Hz.
4. Set the level to −1 dB peak: Select → All, then Effect → Amplify, enter −1 and click OK.
5. Optional, for loop correction: click the end of the track, choose Generate → Silence and enter the time the media player needs to restart the video.
6. Export with File → Export → Export as MP3: choose Constant and 64 kbps mono or 128 kbps stereo. In Edit Metadata Tags, choose Clear to remove all tags.

Upload the MP3 to the AV-Sync Stop in the Tour Editor.

2. Make the video file for the media player

1. Download the AV-Sync track (ZIP with WAV) and extract it. For flexible mode you need different AV-Sync tracks — ask helpdesk@guide-id.com.
2. Keep the track as WAV if you can, and do not change its content in any way. If your video format needs MP3 or AAC, convert it at 192 kbps or higher (MP3) or 128 kbps or higher (AAC). In Audacity: File → Export → Export as MP3, Constant, 192 kbps or higher, Mono.
3. In Avidemux, open the video and choose Audio → Select track. Select track 0, choose Add audio track and open the AV-Sync track.
4. Make sure video and audio both start at 0, and that the AV-Sync track stops when the video ends. The full track is 2 hours long.
5. Select MP4 Muxer as output format and save the video under a new name. Do not use MP4v2 Muxer, because it can cause problems on BrightSign media players.

Optional: room audio

Do this only if the original sound must also play in the room, for example when using the Podcatcher Classic is optional. The AV-Sync track uses one channel, so the other can carry the room sound. The AV-Sync track must stay on the right channel (red RCA plug, to the AV-Sync box); the room sound goes on the left channel (white RCA plug, to the screen or amplifier).

1. In Audacity, open the AV-Sync track and import the audio you saved from the video (File → Import → Audio).
2. On both tracks, choose Split Stereo Track from the track menu.
3. Remove the empty left channel of the AV-Sync track and the right channel of the original sound.
4. On the AV-Sync track, choose Make Stereo Track.
5. Export as MP3: Constant, 192 kbps or higher, Stereo.
6. Add this file to the video as described in step 2.

Related articles

• AV-Sync for Podcatcher Classic — hardware, configuration and testing
• IDentifiers for Podcatcher Classic — types of IDentifier, including the AV-Sync IDentifier
• Synchronizing Podcatcher Classic — get the audio onto the devices