Abstract: A method and system in which a section of a previously encoded digital bit stream is replaced with another section of encoded video. In order to remove a section of encoded video, it is necessary to determine the beginning and ending points of the encoded video in the digitally encoded bit stream. The addresses of the beginning and ending points of the encoded data cannot be simply looked up but are calculated by summing the bits consumed by each picture, the number of bits of the sequence header of each picture, the number of bits of each Group of Pictures (GOP) header, and all stuff bits. In order to encode the video which is to be inserted in place of the removed video, a process is performed which prevents decoding artifacts from appearing. This is accomplished by determining the last P-picture before the edit point and using it as a reference frame for frames after the edit point.

Abstract: A method and system in which a section of a previously encoded digital bit stream is replaced with another section of encoded video. In order to remove a section of encoded video, it is necessary to determine the beginning and ending points of the encoded video in the digitally encoded bit stream. The addresses of the beginning and ending points of the encoded data cannot be simply looked up but are calculated by summing the bits consumed by each picture, the number of bits of the sequence header of each picture, the number of bits of each Group of Pictures (GOP) header, and all stuff bits. In order to encode the video which is to be inserted in place of the removed video, a process is performed which prevents decoding artifacts from appearing. This is accomplished by determining the last P-picture before the edit point and using it as a reference frame for frames after the edit point.

Abstract: An audiovisual encoding system using a multipass video encoder and a plurality of one-pass audio encoders. The number of audio encoders used by the system is equal to the number of audio tracks to be encoded divided by the number of passes required for the video encoding rounded up to the nearest integer, if necessary. The system allows the video encoder and audio encoders to be used at the same time so that the encoding of the video is completed at the same time as the encoding of all audio tracks is completed, using the minimum number of audio encoders.

Abstract: A method and system in which a user manually changes the quality of portions of video frames after the frames have been previously encoded. Regions of one or more frames of video are selected to have an increased quality, a decreased quality, or a quality which should not be altered. After the regions are defined by a user, the frame of video is digitally re-encoded and inserted into the digitally encoded data stream in place of the previously encoded data. In order to easily remove a previously encoded frame from the data steam and replace it with a newly encoded frame having regions of quality defined by the user, it is preferable to have the newly encoded frame consume the same number of bits as the previously encoded frame. Accordingly, if the user desires a region of a frame to have an increased quality, the extra bits necessary to provide the increased quality must be taken from other areas of the frame. This is accomplished by an automatic process which is transparent to the user.

Abstract: A method and system in which a user manually changes the quality of specific time periods of encoded video. After the automatic encoding of video into a compressed digital format, a person editing the encoded video reviews the quality of the video and manually indicates that the quality of specific time periods of the video is to be altered. As the digital storage medium such as an optical disc which stores the encoded video has a finite storage capacity, the total number of bits for the encoded video and the quality of the video is limited. Consequently, in order to increase the quality for one time period, bits must be taken from other time periods. After the editor assigns the qualities to different time periods, a percentage of bits is removed from the time sequences and placed into a bit pool. The new number of bits for the various time periods are calculated using an exponential function and the bits in the bit pool are proportionally distributed to the video frames.