Video compression system
View Patent ↗A video compression system is disclosed that is optimized to take advantage of the types of redundancies typically occurring on computer screens and the types of video loss acceptable to real time interactive computer users. It automatically adapts to a wide variety of changing network bandwidth conditions and can accommodate any video resolution and an unlimited number of colors. The disclosed video compression encoder can be implemented with either hardware or software and it compresses the source video into a series of data packets that are a fixed length of 8 bits or more. Sequences of one or more of these packets create unique encoding “commands” that can be sent over any network and easily decoded (decompressed) with either software or hardware. The commands include 3 dimensional copying (horizontal, vertical and time) and unique efficiencies for screen segments that are comprised of only two colors (such as text). Embodiments are also disclosed that improve the video compression depending on the popularity of pixel colors.
1. A method of encoding digital video for transmission, comprising:
establishing a hierarchy of at least first, second, and third code techniques by ranking the code techniques from highest ranking to lowest ranking, where one of the code techniques is a form, of run-length encoding, and another of the code techniques is a corresponding bit-based encoding of no more and no less than two color states,
reading at least one pixel color, and
applying a selected one of the first, second and third code techniques with preference for the highest ranking code technique in the hierarchy of code techniques.
2. A method according to claim 1 , wherein the first code technique is the form of run-length encoding.
3. A method according to claim 1 , wherein the first code technique is the form of run-length encoding and the second code technique is tire corresponding bit-based encoding.
4. A method according to claim 1 , wherein the first code technique includes a selection from multiple different run-length encoding techniques.
5. A method according to claim 4 , wherein the different run length encoding techniques include copying a pixel color from a previous frame, copying a pixel color from a previous pixel to the left, and copying a pixel color from a pixel color above.
6. A method according to claim 4 , wherein the step of establishing a hierarchy includes establishing a sub-hierarchy between the different run-length encoding techniques in the first code technique.
7. A method according to claim 6 , further including: when (1) the at least one pixel color is encoded using a selected one of the different run-length encoding techniques, and (2) immediately after that run-length encoding, at least one next pixel color thereafter can also be encoded using same one of the different run-length encoding techniques, preempting the established sub-hierarchy between the different run-length encoding techniques and encoding said at least one next pixel color using said same selected one of the different run-length encoding techniques.
8. A method of compressing a stream of digital video information, comprising:
for a current pixel, determining whether the current pixel can be encoded using at least one predefined run length encoding technique, and
(a) if the current pixel, can be encoded using at least one predefined run length encoding technique, then run length encoding at least the current pixel,
(b) if the current pixel cannot be encoded using the at least one predefined run length encoding technique, determining whether the current pixel and a predefined number of subsequent pixels can be drawn from only two pixel colors, and
(i) if the current pixel and a predefined number of subsequent pixels can be drawn from only two pixel colors, then encoding the current pixel and a predefined number of subsequent pixels using a sequence of binary bit states corresponding to the current and subsequent pixel colors.
9. A method according to claim 8 , further comprising, after (b)(i):
(ii) if the current pixel and a predefined number of subsequent pixels cannot be drawn from only two pixel colors, then encoding the current pixel into one or more bytes identifying the current pixel color.
10. A method according to claim 8 , wherein said at least one predefined run-length encoding technique includes: copying said current pixel from a corresponding pixel in a prior frame.
11. A method according to claim 8 , wherein said at least one predefined run-length encoding technique includes: copying said current pixel from a pixel in a current frame having an established locational relationship with the current pixel.
12. A method according to claim 8 , wherein said at least one predefined run-length encoding technique includes: copying an old pixel from a prior frame, copying a pixel to the left of the current pixel, and copying a pixel above the current pixel.
13. A method according to claim 12 , further including: after run length encoding in (a), for a next pixel, determining whether the next pixel can be encoded using the same predefined run length encoding technique used for a prior pixel run, and if the next pixel can be encoded using the same predefined run-length encoding technique, then using said same run-length encoding technique to encode said next pixel.
14. A method of encoding digital video for transmission, comprising:
establishing a hierarchy of rankings, from highest ranking code technique to lowest ranking code technique, between a first code technique in the form of run-length encoding and a second code technique as a corresponding bit-based encoding of no more and no less than two color states,
reading at least one pixel color,
applying a selected one of the first and second code techniques with preference for the highest ranking code technique in the hierarchy.
15. A method according to claim 14 , wherein the step of reading includes:
reading a plurality of pixel colors; and wherein the applying step includes:
applying the selected one of the first and second code techniques to the plurality of pixel colon with preference for the highest ranking code technique in the hierarchy.
16. A method according to claim 14 , wherein the step of reading includes:
reading a consecutive sequence of pixel colors, and wherein the applying step includes:
applying the selected one of the first and second code techniques to the consecutive sequence of pixel colors with preference for the highest ranking code technique in the hierarchy.
17. A method according to claim 16 , wherein the consecutive sequence of pixel colors extends for as long as one of the first and second code techniques applies.