Abstract: The invention of the present application provides data compression and archival features for data that has previously been transformed and compressed. In a first aspect of the present invention, compressed data that has previously been transformed and compressed is received, and coefficients in the compressed data are selected and discarded to reduce the amount of storage space required by the compressed data. In another aspect, the compressed data has previously been sub-sampled by a wavelet transform, and wavelet coefficients in the compressed data are selected and discarded. In another aspect, wavelet coefficients in the compressed data are dequantized, wavelet coefficients in the compressed data having less value for the data are selected, and the wavelet coefficients are requantized so as to cause more loss of data for the selected coefficients to reduce the amount of storage space required by the compressed data.

Abstract: Methods and systems for image and video enhancement and data-loss recovery using wavelet transforms are disclosed. A wavelet transformed image is defined as multiple sections, where one section is the original image, and coefficients are estimated for each other section using information obtained from that section. An inverse wavelet transform on the wavelet transformed image obtains an enlarged image. For obtaining a high resolution video frame, one section is the original video frame, and coefficients are estimated for each other section using information from a lower level wavelet transform of a corresponding section of a past or future frame of the video sequence. For recovery of data lost from transmitted original data, the locality of the lost data is determined in lower and higher levels of a wavelet transform tree, and information at the locality in the lower and higher levels is used to estimate the lost data.

Abstract: A system and a method for wavelet-based low bitrate video coding is provided. The system and method of this invention processes each frame of a video sequence based on its content. The discrete wavelet transform of each frame is taken separately. If the difference between the contents of a first frame and a second frame is above a threshold, then the wavelet transformed second frame is quantized and lossless encoded. If the difference is less than a threshold, then motion estimation is employed in wavelet domain. Then the difference between the wavelet transformed second frame and the motion compensated wavelet transformed second frame is quantized and lossless encoded. The quantization is applied by using dynamic adjustment. The quantization tables are optimized based on the coded frame characteristics. In addition to the coded frames, the lossless coded motion vectors are also transmitted to the decoder unit.

Abstract: A method and system for moving object and region detection in video compressed using a wavelet transform is disclosed. A plurality of images are inputted to the system in wavelet compressed format in time series. In a first aspect, a method and system determines the motion by comparing the wavelet transform of the current image and the wavelet transform of the previous image of the video. Difference between the wavelet coefficients of the current and previous images indicate motion. Moving regions in the video can be estimated by determining the wavelet coefficients of the current image frame, which are different from the wavelet coefficients of the previous image frame. The method and system does not include performing an inverse wavelet transform on the wavelet transformed image. This leads to a computationally efficient method and a system compared to the existing motion estimation methods.

Abstract: A method and system for characterizing the motion of moving objects in video is disclosed. The video can be either compressed or uncompressed form. A typical video scene contains foreground and background objects. Foreground objects temporarily stay in the video. However, a left object or stopped object becomes part of the background scene and remains in the video forever. A plurality of images is inputted to the system in time series. A method and system determines left objects or stopped objects by comparing the background image estimated from the current image of the video with the background estimated from previous images of the video. Difference between the current and previous background images indicates a left or stopped object. Other objects, which do not modify the background image are determined as transitory objects. Background scene of a video can be estimated using the compressed video data as well.

Abstract: The invention of the present application provides data compression and archival features for data that has previously been transformed and compressed. In a first aspect of the present invention, compressed data that has previously been transformed and compressed is received, and coefficients in the compressed data are selected and discarded to reduce the amount of storage space required by the compressed data. In another aspect, the compressed data has previously been sub-sampled by a wavelet transform, and wavelet coefficients in the compressed data are selected and discarded. In another aspect, wavelet coefficients in the compressed data are dequantized, wavelet coefficients in the compressed data having less value for the data are selected, and the wavelet coefficients are requantized so as to cause more loss of data for the selected coefficients to reduce the amount of storage space required by the compressed data.

Abstract: Methods and systems for image and video enhancement and data-loss recovery using wavelet transforms are disclosed. A wavelet transformed image is defined as multiple sections, where one section is the original image, and coefficients are estimated for each other section using information obtained from that section. An inverse wavelet transform on the wavelet transformed image obtains an enlarged image. For obtaining a high resolution video frame, one section is the original video frame, and coefficients are estimated for each other section using information from a lower level wavelet transform of a corresponding section of a past or future frame of the video sequence. For recovery of data lost from transmitted original data, the locality of the lost data is determined in lower and higher levels of a wavelet transform tree, and information at the locality in the lower and higher levels is used to estimate the lost data.

Abstract: A system and a method for wavelet-based low bitrate video coding is provided. The system and method of this invention processes each frame of a video sequence based on its content. The discrete wavelet transform of each frame is taken separately. If the difference between the contents of a first frame and a second frame is above a threshold, then the wavelet transformed second frame is quantized and lossless encoded. If the difference is less than a threshold, then motion estimation is employed in wavelet domain. Then the difference between the wavelet transformed second frame and the motion compensated wavelet transformed second frame is quantized and lossless encoded. The quantization is applied by using dynamic adjustment. The quantization tables are optimized based on the coded frame characteristics. In addition to the coded frames, the lossless coded motion vectors are also transmitted to the decoder unit.