Generation and detection of private metadata in an encoded video transport stream

A rate shaping device, comprising:

• a metadata extractor that extracts predefined metadata from a video transport stream, wherein the predefined metadata specifies at least one macroblock defining a subset of a frame in the video transport stream that is not to be altered during statistical remultiplexing;
• a decoder that converts the video transport stream into original macroblock coefficients;
• a quantizer arrangement that re-quantizes the macroblock coefficients at a quantization level different from their original quantization level;
• a macroblock selector that receives the original macroblock coefficients from the decoder and the re-quantized macroblock coefficients from the quantizer arrangement;
• a macroblock detector that receives a signal from the metadata extractor indicating the at least one macroblock defining the subset of the frame that is not to be altered during statistical remultiplexing, and compares the received signal with a current macroblock being processed;
• and
• a macroblock selector that:
• receives the original macroblock coefficients from the decoder and the re-quantized macroblock coefficients from the quantizer arrangement, and
• selects, for each macroblock defining the subset of the frame in the video transport stream, either the corresponding original macroblock coefficient or the re-quantized macroblock coefficient based on the comparison of the macroblock detector.

A video transmitter, comprising:

• an A/V codec for receiving video programming and generating a digital video stream;
• a PSI module configured to receive private metadata associated with the video programming, generate at least one PSI table and insert a descriptor in the PSI table indicating the presence of the private metadata, wherein the private metadata identifies one or more macroblocks defining a subset of at least one frame in a plurality of encoded video streams, to be multiplexed into a transport stream, with an encoding that is to be preserved when re-encoding the encoded video streams during statistical remultiplexing;
• and
• a metadata insertion module configured to receive the digital video stream and the private metadata and insert the private metadata into a prescribed portion of the digital video stream specifying the one or more identified macroblocks that define a subset of at least one frame for which, when remultiplexing the plurality of encoded video streams into the transport stream, the encoding of the corresponding portion of an image should be preserved.

At least one non-transitory computer-readable medium encoded with instructions which, when executed by a processor, performs a method including:

• extracting descriptor information indicating where predefined metadata is embedded in at least one of the plurality of encoded video streams, wherein the predefined metadata identifies one or more macroblocks defining a subset of at least one frame in the plurality of encoded video streams with an encoding that is to be preserved when re-encoding the encoded video streams during statistical remultiplexing;
• identifying the one or more macroblocks in the plurality of encoded video streams with the encoding that is to be preserved during statistical remultiplexing;
• and
• preserving the encoding of the one or more identified macroblocks that define a subset of at least one frame when multiplexing the plurality of encoded video streams into the transport stream to preserve a portion of an image during the statistical remultiplexing.