Video image data processing in electronic devices
In some embodiments, an electronic device for compressing video image data includes a housing, an image sensor, a memory device, and one or more processors. The image sensor can generate image data from light incident on the image sensor. The one or more processors can transform the image data to obtain transform coefficients, quantize the transform coefficients, encode the quantized transform coefficients, and store the quantized transform coefficients to the memory device. The one or more processors can encode the quantized transform coefficients at least by determining a range of multiple ranges in which one transform coefficient is included, determining a value within the range to which the one transform coefficient corresponds, encoding using a first algorithm the range as a range code, and encoding using a second algorithm the value as a value code.
1. An electronic device, comprising:
a housing;
an image sensor configured to generate image data from light incident on the image sensor;
a memory device; and
one or more processors configured to:
apply a lossy transform to the image data, such that at least some digital values in an input domain are lumped to a single value in an output domain;
transform the image data to obtain transform coefficients;
quantize the transform coefficients to obtain quantized transform coefficients including a first quantized transform coefficient and a second quantized transform coefficient different from the first quantized transform coefficient;
encode the quantized transform coefficients to obtain encoded coefficients; and
store the encoded coefficients to the memory device in a compressed file, wherein the compressed file is not tonally processed, and tonal processing on the compressed file is deferred.
2. The electronic device of claim 1 , wherein the one or more processors are configured to quantize the transform coefficients by at least using at least a first quantization table and a second quantization table different from the first quantization table.
3. The electronic device of claim 1 , wherein the one or more processors are configured to apply noise filtering to the image data.
4. The electronic device of claim 1 , wherein the compressed file comprises YUV data.
5. The electronic device of claim 1 , wherein the lossy transform comprises a piecewise linear function that converts the image data from a first bit-width to a second bit-width.
6. The electronic device of claim 1 , wherein the one or more processors are configured to quantize the transform coefficients using a first algorithm and a second algorithm different than the first algorithm.
7. The electronic device of claim 6 , wherein the first algorithm comprises determining Huffman codes and the second algorithm comprises determining Golomb codes.
8. The electronic device of claim 6 , wherein the one or more processors is configured to vary the first algorithm during processing of the image data.
9. The electronic device of claim 8 , wherein the one or more processors is configured to vary the first algorithm from processing a first frame of the image data to processing a second frame of the image data.
10. The electronic device of claim 8 , wherein the second algorithm remains constant during processing of the image data by the one or more processors.
11. The electronic device of claim 1 , wherein the one or more processors is configured to transform the image data using a discrete cosine transform.
12. The electronic device of claim 1 , wherein the one or more processors is configured to encode the quantized transform coefficients at least by encoding DC coefficients of the quantized transform coefficients differently from AC coefficients of the quantized transform coefficients.
13. The electronic device of claim 1 , wherein the electronic device is a mobile phone.
14. The electronic device of claim 1 , wherein the housing is configured to enclose the image sensor, the memory device, and the one or more processors, and the housing is configured to removably attach to a electronic device.
15. The electronic device of claim 1 , wherein the compressed file comprises still image data.
16. The electronic device of claim 1 , wherein the compressed file comprises motion video image data.
17. The electronic device of claim 1 , further comprising a display configured to present holographic images generated by the one or more processors from the image data.
18. A method of capturing an processing image data, comprising:
with an image sensor, generating image data from light incident on the image sensor;
applying a transform to the image data such that at least some digital values in an input domain are lumped to a single value in an output domain;
compressing the image data, said compressing comprising:
transforming the image data to obtain transform coefficients;
quantizing the transform coefficients to obtain quantized transform coefficients including a first quantized transform coefficient and a second quantized transform coefficient different from the first quantized transform coefficient; and
encoding the quantized transform coefficients to obtain encoded coefficients; and
storing the encoded coefficients to a memory device in a compressed file, wherein the compressed file is not tonally processed, and tonal processing on the compressed file is deferred.
19. The method of claim 18 , further comprising applying noise filtering to the image data.
20. The method of claim 18 , wherein the compressed file comprises YUV data.