Bitrate: Bitrate is the amount of data being decoded per second. Depending on your pixel dimension and delivery method, the bitrate will vary. One way to reduce file size is to lower the bitrate, but you may actually notice a difference in quality. Here are some recommended bitrates:
Dimension |
Delivery |
Avg Bit Per Sec |
320X240 | Web | 400 kbps |
720X480 | DVD | 4000-5000 kbps |
1920X1080 | Blu-ray | 50,000 kbps (50 mbps) |
3840×2160 | HDTV | 85 mbps |
7680×4320 | HDTV | 360 mbps |
Pixel Dimension (or Video Resolution): In short, this is the width and height of your video, and it can be resized to suit your needs. Here are some examples:
Format | Dimension | Aspect Ratio |
PDA | 320x240 | 4:3 |
VGA | 640x480 | 4:3 |
DVD (NTSC) | 720x480 | 4:3 |
DVD (PAL) | 720x576 | 4:3 |
XGA | 1024x768 | 4:3 |
HD | 1280x720 | 16:9 |
FULL HD | 1920x1080 | 16:9 |
4K ULTRA | 3840×2160 | 16:9 |
8K ULTRA | 7680×4320 | 16:9 |
Another thing to consider is if you to try to show a widescreen video on a standard display, it could either have the ends cropped off or be squished down to fit the size. By Letterboxing a 16:9 video, you recreate the 4:3 aspect ratio.
Here is a handy aspect ratio calculator for determining your resolution, or vice-versa.
Interlace: When video is intended for television, it is interlaced. Each frame is made up of two fields of interlaced lines. On a computer monitor this is seen as a comb effect because one field is 1/60 of a second ahead of the other. If your video program provides the option, interlaced video should be deinterlaced before encoding..
Two-pass: Videos can be encoded in one sweep (single pass), but some tools can also encode videos in two passes. In the first pass, the video is analyzed to see which sections require a higher or a lower bitrate. In the second pass, the actual encoding is done. Two-pass encoding takes longer but creates a video roughly 75% to 95% of the original file size at the same quality.
Media conversion software, or transcoders, come in all shapes and sizes. Many are free, many are cross-platform. Some will only import certain formats, while others may have limited output options. Some will handle batch processing and others offer editing options.
On this page are video examples of how to convert video file formats and how to rip a DVD using Format Factory, one of the many free transcoders available for Windows.
When converting video from one format to another, it is essential to note the following three settings:
Refer to the glossary on the left as a guide for these settings.