Video Streaming and Compression
STEP 1: Import and trim your video
To import your video source, go to the File pull-down menu and choose Open Files (PC and Mac). Navigate to your source and either choose Open or drag the video source right into the Main Window (Mac).
Once your video is seen in the Main Window you can play, pause or trim your source. To trim your video, move the play head to the location where you would like your trim to start and press the I key. Move to your ending point and press the O key. Next, go to the Edit pull-down menu and select Trim.
STEP 2: Make adjustments to audio volume, brightness and contrast
Once your video is trimmed you can choose how you want to export it. To do this, go to the File pull-down menu and select Export to DV or Export to QuickTime. Once you’ve selected which format you’d like to convert your file to, select the Adjustments button in the Exporter dialog window. This lets you adjust Audio Volume, Brightness and Contrast. A good starting point is to adjust Brightness to 10, Contrast to about 115 percent and Audio Volume to +6.0 dB. Click the OK button when you’re done.
STEP 3: Crop your source
If you need to crop off black edges, make sure you choose crop values that match your output aspect ratio. In this image the cropping is for a 4:3 aspect ratio. Left and Right crop values in pixels are set to 2, which equals 4 pixels total. Top value is 2 and Bottom value is 1, which equals 3 pixels; the cropping matches the 4:3 aspect ratio.
STEP 4: Deinterlace your video
This image, created using Sorenson Squeeze, shows the benefits of deinterlacing your video. Getting rid of one of the video fields makes for easier and better compression. Notice that the video to the right shows interlacing and the video to the left shows the results of deinterlacing. In the Exporter dialog window check the Deinterlace Video button to deinterlace your video.
STEP 5: Choose a video codec
Use the default for AVI files to choose a codec. For QuickTime videos you can choose DV/DVCPPRO NTSC, Photo-JPEG, Motion JPEG A and Motion JPEG B codecs. Push the Quality setting to 100 percent to get the best quality.
STEP 6: Choose and audtio codec
Under Audio Codec, choose Uncompressed. This way you can apply your audio codec in your compression application.
STEP 7: Export your video
When you’re ready to export your video, select the Make DV or Make Movie button in the Export Dialog Window and navigate to your desired file destination. During export, you’ll notice a Preview Window displayed along with a Progress Window. Both windows will close when your video is finished exporting.
STEP 8: Create a preset
To create a preset of your export setting, click the Preset button. There, you’ll see a New Preset dialog window displayed; go ahead and click the Yes button. Next, give your Preset a name and click OK. In the preset pop-up menu select your created preset by clicking the Load button. Now you’re ready to export your video.
Derrick Says Keep in Mind…
MPEG Streamclip is a powerful yet free converter, player and editor for Mac and Windows. Some of the files that users can import into MPEG Streamclip are QuickTime, DV, AVI, MPEG-2 and VOB files. Windows users won’t be able to batch export multiple files, however. Once your video files are pre-processed, you can save them and use them for your current compression job or archive them for future compression projects. If you need to re-encode these video clips with newer codecs, MPEG Streamclip will make this easy. If your end result is video for Web streaming, exporting to AVI and QuickTime are both good options. You can easily encode these files in many compression applications. Remember to keep your video at the original frame size during pre-processing.
One last note: The various versions of the QuickTime codec provide a great way to store video content that needs to go into a compression application. Why? QuickTime compresses video spatially. Even older QuickTime codecs will give you exceptional quality at the highest quality setting.
To download a copy of MPEG Streamclip for Mac or Windows, go to www.squared5.com.
7575 Dr. Phillips Blvd., Suite 120
Orlando, FL 32819
About Derrick Freeman: Derrick has been compressing video for seven years and has spent five years researching streaming media. He is a beta tester for video compression applications and writes video streaming and compression articles for GeniusDV.com. He also manages the video streaming training and consulting division for GeniusDV.