Compression with doppler enhancement
View Patent ↗Methods, medium, and machines which compress, enhance, encode, transmit, decode, decompress and display digital video images. Real time compression is achieved by sub-sampling each frame of a video signal, filtering the pixel values, and encoding. Real time transmission is achieved due to high levels of effective compression. Real time decompression is achieved by decoding and decompressing the encoded data to display high quality images. A receiver can alter various setting including, but not limited to, the format for the compression, image size, frame rate, brightness and contrast. In a Doppler improvement aspect of the invention, Doppler velocity scales are incorporated into grayscale compression methods using two bits. Variable formats may be selected and Doppler encoding can be turned on and off based on the image content. Frames or sets of pixels may be distinguished by automated analysis of the characteristics of an image, such as the presence of Doppler enhanced pixels.
1. A method comprising:
determining, by an encoder, whether a pixel of a Doppler enhanced grayscale image is a grayscale pixel or a Doppler enhancement pixel, by determining a color scale of the pixel, wherein a Doppler enhanced grayscale image comprises grayscale pixels and Doppler enhancement pixels, and wherein a Doppler enhanced grayscale image is captured as a color image;
setting, by the encoder, a flag to indicate whether the pixel has a grayscale value or is a Doppler enhancement pixel, based on a result of said determining; and
generating and outputting, by the encoder, a codeword that encodes the pixel value and the flag.
2. The method of claim 1 , further comprising determining, by the encoder, a Doppler scale of the pixel, on determining that the pixel is a Doppler enhancement pixel.
3. The method of claim 2 , wherein the flag is a first flag, the method further comprises setting, by the encoder, a second flag to indicate the determined Doppler scale, and generating and outputting comprises generating and outputting a codeword that encodes the pixel value, the first flag and the second flag.
4. The method of claim 3 , wherein setting a first flag comprises setting a first bit of a data word and setting a second flag comprises setting a second bit of the data word.
5. The method of claim 3 , wherein generating comprises retrieving the codeword from a table.
6. The method of claim 2 , wherein determining a Doppler scale of the pixel comprises determining a selected one of a red scale or a blue scale.
7. The method of claim 1 , wherein the image is a selected one of a medical image or a weather image.
8. The method of claim 1 , wherein the pixel comprises a plurality of color components, and determining comprises comparing values of the color components.
9. The method of 8 , wherein determining comprises determining the pixel as a grayscale pixel if the color component values are equal, and determining the pixel as a Doppler enhancement pixel if the color component values are not equal.
10. The method of claim 1 further comprising:
counting, by the encoder, a number of Doppler enhanced pixels in the image; and
turning on, by the encoder, Doppler enhanced encoding when a result of the counting is greater than zero.
11. The method of claim 10 , further comprising turning on, by the encoder, grayscale encoding when the result of the counting is zero.
12. The method of claim 1 , wherein generating comprises retrieving the codeword from a table.
13. The method of claim 1 , wherein the image is a video frame.
14. An apparatus comprising:
an encoder configured to determine a color scale of a pixel of a Doppler enhanced grayscale image, to determine whether the pixel is a grayscale pixel or a Doppler enhancement pixel, set a flag to indicate whether the pixel has a grayscale value or is a Doppler enhancement pixel, based on a result of the determination, generate and output a codeword that encodes the pixel value and the flag; and
a transmitter coupled with the encoder and configured to transmit the codeword;
wherein a Doppler enhanced grayscale image comprises grayscale pixels and Doppler enhancement pixels; and
wherein a Doppler enhanced grayscale image is captured as a color image.
15. The apparatus of claim 14 , wherein the encoder is further configured to determine a Doppler scale of the pixel, on determination that the pixel is a Doppler enhancement pixel.
16. The apparatus of claim 15 , wherein the flag is a first flag, and the encoder is further configured to set a second flag to indicate the determined Doppler scale, generate and output a codeword that encodes the pixel value, the first flag and the second flag.
17. The apparatus of claim 16 , wherein the encoder is configured to set a first bit of a data word to indicate whether the pixel has a grayscale value or is a Doppler enhancement pixel and set a second bit of the data word to indicate a Doppler scale of the pixel.
18. The apparatus of claim 16 , further comprising a storage device configured to store a table that includes the codeword.
19. The apparatus of claim 14 , wherein the pixel comprises a plurality of color components, and the encoder is configured to compare values of the color components to determine whether the pixel has a grayscale pixel value or a Doppler enhancement pixel.
20. The apparatus of 19 , wherein the encoder is configured to determine the pixel as a grayscale pixel if the color component values are equal, and determine the pixel as a Doppler enhancement pixel if the color component values are not equal.
21. The apparatus of claim 14 further comprising a counter coupled with the encoder, and configured to count a number of Doppler enhanced pixels in the image.
22. The apparatus of claim 21 wherein the encoder is further configured to turn on Doppler enhanced encoding when a result of the count is greater than zero, and turn on grayscale encoding when the result of the count is zero.
23. An article of manufacture comprising:
a non-transitory computer-readable storage device; and
a plurality of programming instructions stored in the storage device, and configured to enable an apparatus to perform a number of operations, in response to execution of the programming instructions by the apparatus, wherein the operations include:
determining whether a pixel of a Doppler enhanced grayscale image is a grayscale pixel or a Doppler enhancement pixel, by determining a color scale of the pixel, wherein a Doppler enhanced grayscale image comprises grayscale pixels and Doppler enhancement pixels, and wherein a Doppler enhanced grayscale image is captured as a color image;
setting a flag to indicate whether the pixel has a grayscale value or is a Doppler enhancement pixel, based on a result of said determining; and
generating and outputting a codeword that encodes the pixel value and the flag.
24. The article of claim 23 , wherein the operations further comprise determining a Doppler scale of the pixel, on determining that the pixel is a Doppler enhancement pixel.
25. The article of claim 24 , wherein the flag is a first flag, the operations further comprise setting a second flag to indicate the determined Doppler scale, and generating and outputting comprises generating and outputting a codeword that encodes the pixel value, the first flag and the second flag.