THL Toolbox > Audio-Video > Technical Processing of Audio-Video - Log, Edit and Compress > Compressing Titles

Compression of Audio-Visual Titles Manual

Contributor(s): Eric Woelfel.

This present document is a manual for compressing audio-video manuals, but we also offer a Compression Checklist to print out and use for quick reference.

Export the media

The process of exporting the edited videos produces a video that is more easily viewed over the internet. Export/compression reduces the file size (and quality) of the video file so that it is of a manageable size to access over the internet as well as for use within an ordinary computer. THL has strict standards for creating compressions to assure users enjoy the best quality video possible at current bandwidths. Check back to this section often because as video compression technology and techniques continue to improve, we will adopt new standards. The documentation will describe the export process using Final Cut Pro 5 presets however some of the technical parameters are also provided to allow a media processor to create compressions that meet THL standards on a platform other than a Mac.

1. Create the folder structure for the new compressions on your local hard drive. The three video files will all have the same file name so it is essential that there are three different folders created to receive the video compressions. See the tip below for instructions for naming the local folders for the compressions. The following instructions will assume you are using the file names suggested below. TIP: Compressed videos are best archived on your local hard drive by creating a folder structure that mirrors the folder structure on THL’s server. The audio files exist in a folder named “audio” and the video files exist in three different folders nested in a “media” folder; "high", "low" and "super high".
2. Select all the sequences in the Browser window by Apple + left clicking on the sequences.
3. Right click on one of the sequences and select the “Batch Export” option.
4. The Export Queue window will open up and your sequences will be placed in a batch. Left click and drag the selected sequences in the Browser window to the Export Queue to create a second batch. Repeat this process two more times so all your sequences exist in duplicate in four batches in the Export Queue window, Batch 1, Batch 2, Batch 3 and Batch 4.

1. Set the settings for the “super high” compressions

1. Highlight the first batch in the Export Queue by left clicking on the Batch 1 folder icon then left click on the “Settings…” button on the bottom of the Export Queue window.
2. Left click the “Set Destination” button on the settings window and navigate to the “super high” folder in the Choose a Folder browser and click the “Choose” button.
3. Select “MPEG-4” from the “Format:” drop down menu.
4. Select “LAN/Intranet” from the “Settings:” drop down menu.
5. Left click on the “Set Naming Options…” button and check the “Add File Type Extension” box then click “OK”.
6. Left click on the “OK” button.

TIP: Use the following settings to make THL-standard super high compression in a program other than Final Cut Pro:

• Video Format: H.264
• Data Rate: 1372 kbits/sec
• Image Size: 640 x 480 VGA
• Key Frame: Every 150 frames
• Audio: AAC-LC Music, Stereo, 128 kbps
• Streaming (hinting): none

2. Set the settings for the “high” compressions

1. Highlight the second batch in the Export Queue by left clicking on the Batch 2 folder icon then left click on the “Settings…” button on the bottom of the Export Queue window.
2. Left click the “Set Destination” button on the settings window and navigate to the “high” folder in the Choose a Folder browser and click the “Choose” button.
3. Select “MPEG-4” from the “Format:” drop down menu.
4. Select “Broadband – High” from the “Settings:” drop down menu.
5. Left click on the “Set Naming Options…” button and check the “Add File Type Extension” box then click “OK”.
6. Left click on the “OK” button.

TIP: Use the following settings to make THL-standard high compression in a program other than Final Cut Pro:

• Video Format: H.264
• Data Rate: 672 kbits/sec
• Image Size: 480 x 360 VGA
• Key Frame: Every 150 frames
• Audio: AAC-LC Music, Stereo, 128 kbps
• Streaming (hinting): none

3. Set the settings for the “low” compressions

1. Highlight the third batch in the Export Queue by left clicking on the Batch 3 folder icon then left click on the “Settings…” button on the bottom of the Export Queue window.
2. Left click the “Set Destination” button on the settings window and navigate to the “low” folder in the Choose a Folder browser and click the “Choose” button.
3. Select “MPEG-4” from the “Format:” drop down menu.
4. Select “Broadband – Medium” from the “Settings:” drop down menu.
5. Left click on the “Set Naming Options…” button and check the “Add File Type Extension” box then click “OK”.
6. Left click on the “OK” button.

TIP: Use the following settings to make THL-standard low compression in a program other than Final Cut Pro:

• Video Format: H.264
• Data Rate: 220 kbits/sec
• Image Size: 320 x 240 VGA
• Frame Rate: 15
• Key Frame: Every 75 frames
• Audio: AAC-LC Music, Stereo, 80 kbps
• Streaming (hinting): none

4. Set the settings for the “audio” compressions

NOTE: Audio compressions should only be completed for titles with substantive value to the audio track: interviews, dialogues, songs, song & dance, musical performance, lecture, and so forth. You do NOT need to run audio compressions for other titles. For example, you need not run an audio compression for a title comprised of panoramic views of the Yarlung Valley, if the soundtrack is just ambient noise such as wind blowing. If you are unsure, check with David Germano or another THL A/V staff member.

Audio is processed in two parts; first the sequences are exported from Final Cut Pro, and then the exported audio is compressed into MPEG-3s in Apple iTunes.

1. Highlight the fourth batch in the Export Queue by left clicking on the Batch 4 folder icon then left click on the “Settings…” button on the bottom of the Export Queue window.
2. Left click the “Set Destination” button on the settings window and navigate to the “audio” folder in the Choose a Folder browser and click the “Choose” button.
3. Select “AIFF” from the “Format:” drop down menu.
4. Select “44.1 kHz 16 bit Stereo” from the “Settings:” drop down menu.
5. Left click on the “OK” button.

TIP: Use the following settings to make THL-standard audio compression in a program other than Final Cut Pro:

• Format: Linear PCM
• Rate: 44.100 kHz
• Sample Rate Converter Settings:
• Quality: Normal
• Linear PCM Settings:
• Sample size: 16 bits

5. Export the sequences

This step will produce the final video compression that will be used on the THL’s AVDB. The compression time will vary depending on the length of the video and the processing speed and memory of your computer. Please note you will not be able to use your computer while the videos are being compressed.

1. Close all programs other than Final Cut Pro.
2. Click the “Export” button at the bottom of the Export Queue window.

TIP: If you would like to export all the batches together in one batch, use the Apple+A funtion to select all the batches than click the "Export" button to begin.

6. Compress MP3’s in iTunes

1. Navigate to the “audio” folder for your recent compressions on your local hard drive.
2. Select all the files in the audio folder by apple + left clicking on all the files or by using the apple + a shortcut.
3. Open iTunes and left click + drag all the audio files into iTunes.
4. After the files have been imported into iTunes select all the files then right click on one of the selected files. Select the “Convert Selection to MPEG-3” option.
5. After the files finish compressing, right click on one of the new MPEG-3 files and select the “Show Song File” option.
6. Select all the MPEG-3 files in the newly opened folder and copy them to the audio folder.
7. You can now delete the AIFF audio files in the audio folder.

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