Apparatus and method for processing an image signal in a digital broadcast receiver

• US 20060087585A1
• Filed: 10/26/2005
• Published: 04/27/2006
• Est. Priority Date: 10/26/2004
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Kim, Hwan, Park, Wei-Jin, Seo, Jeong-Wook, Lee, Dong-Yul
• Granted Patent: US 7,986,846 B2
• Time in Patent Office: Days
• US Class Current: 348/385.100
• CPC Class Codes: H04N 19/122 Selection of transform size, e.g. 8x8 or 2x4x8 DCT; Selection of sub-band transforms of varying structure or type
• CPC Class Codes: H04N 19/132 Sampling, masking or truncation of coding units, e.g. adaptive resampling, frame skipping, frame interpolation or high-frequency transform coefficient masking
• CPC Class Codes: H04N 19/156 Availability of hardware or computational resources, e.g. encoding based on power-saving criteria
• CPC Class Codes: H04N 19/16 for a given display mode, e.g. for interlaced or progressive display mode
• CPC Class Codes: H04N 19/162 User input
• CPC Class Codes: H04N 19/18 the unit being a set of transform coefficients
• CPC Class Codes: H04N 19/1887 the unit being a variable length codeword
• CPC Class Codes: H04N 19/44 Decoders specially adapted therefor, e.g. video decoders which are asymmetric with respect to the encoder
• CPC Class Codes: H04N 19/46 Embedding additional information in the video signal during the compression process H04N19/517, H04N19/68, H04N19/70 take precedence
• CPC Class Codes: H04N 19/48 using compressed domain processing techniques other than decoding, e.g. modification of transform coefficients, variable length coding [VLC] data or run-length data motion estimation in a transform domain H04N19/547; processing of decoded motion vectors H04N19/513
• CPC Class Codes: H04N 19/51 Motion estimation or motion compensation
• CPC Class Codes: H04N 19/59 involving spatial sub-sampling or interpolation, e.g. alteration of picture size or resolution
• CPC Class Codes: H04N 19/61 in combination with predictive coding
• CPC Class Codes: H04N 21/25808 Management of client data terminal profiles in network data switching protocols H04L67/303
• CPC Class Codes: H04N 21/2662 Controlling the complexity of the video stream, e.g. by scaling the resolution or bitrate of the video stream based on the client capabilities
• CPC Class Codes: H04N 21/41407 embedded in a portable device, e.g. video client on a mobile phone, PDA, laptop constructional details of equipment or arrangements specially adapted for portable computer application G06F1/1626; arrangements specially adapted for mobile receivers in broadcast systems H04H20/57
• CPC Class Codes: H04N 21/434 Disassembling of a multiplex stream, e.g. demultiplexing audio and video streams, extraction of additional data from a video stream; Remultiplexing of multiplex streams; Extraction or processing of SI; Disassembling of packetised elementary stream demultiplexing of data packets for data networks, e.g. RTP/UDP H04L65/00
• CPC Class Codes: H04N 21/4402 involving reformatting operations of video signals for household redistribution, storage or real-time display details of conversion of video standards at pixel level H04N7/01; video transcoding H04N19/40; adapting incoming signals to the display format of the display terminal G09G5/005; media handling at the source in data packet switching networks H04L65/764
• CPC Class Codes: H04N 21/440263 by altering the spatial resolution, e.g. for displaying on a connected PDA
• CPC Class Codes: H04N 21/4621 Controlling the complexity of the content stream or additional data, e.g. lowering the resolution or bit-rate of the video stream for a mobile client with a small screen arrangements for using the results of monitoring on user's side in broadcast systems H04H60/65; flow control in packet networks H04L47/10

Abstract

A method and apparatus for decoding a coded video data in a digital broadcast receiver. The method includes: determining a resizing control signal for resizing a received video data; analyzing header information from a decoded video stream and separating and outputting a video data; resizing the separated video data by the resizing control signal and decoding the resized video data into an original pixel data with an original data size by using a variable length table; dequantizing the decoded video data; resizing and converting the dequantized frequency-domain video data into a two dimensional spatial domain video data by the resizing control signal; movement compensating for movement of a movement compensation data corresponding to one of the inverse-transformed video data and the separated video data; and converting outputs of the inverse transform unit and the movement compensation unit into display data for a display unit.

Claims

1. A video decoder of a digital broadcast receiver, comprising:

a resizing control unit for generating a resizing control signal for resizing a received video data;

a header analyzer for analyzing header information from a decoded video stream and separating and outputting video data;

a variable length decoder for decoding the video data output from the header analyzer into an original pixel data with an original data size using a variable length table;

a dequantizer for dequantizing the decoded video data;

an Inverse Transform (IT) unit for resizing and converting the dequantized frequency-domain video data into a two dimensional spatial domain video data using the resizing control signal; and

a movement compensator unit for compensating for movement of a movement compensation data corresponding to one of the inverse-transformed video data and the separated video data.

2. The video decoder as claimed in claim 1, wherein the inverse transform unit is an Inverse Discrete Cosine Transform (IDCT) unit.

3. The video decoder as claimed in claim 2, wherein the IDCT unit comprises:

a Y axis resizer for selecting an N point inverse discrete cosine transformer using a Y axis control signal of the resizing control signal;

an N number of Y axis inverse discrete cosine transformers including the selected N point inverse discrete cosine transformer for inverse cosine transforming Y axis video data in a resized area;

an X axis resizer for selecting an M point inverse discrete cosine transformer using an X axis control signal of the resizing control signal; and

an M number of X axis inverse discrete cosine transformers including the selected M point inverse discrete cosine transformer for inverse cosine transforming X axis video data in a resizing area, the X axis video data being stored in a Y buffer.

4. The video decoder as claimed in claim 1, wherein the variable length decoder comprises:

a resizer for resizing the separated video data based on the resizing control signal;

a table converter for decoding the received variable length coded video data into a video data with the original size; and

a buffer for storing the video data decoded by the table converter,

wherein the resizer controls the table converter to decode data in blocks included in the resizing area set by the resizing control signal and controls the buffer to store the video data in the resizing area.

5. The video decoder as claimed in claim 1, wherein the movement compensator unit comprises:

a buffer for storing a received movement compensation vector value;

a previous image memory for storing a previous image in order to compare the movement compensation vector value;

a next image memory for storing a next image in order to compare the movement compensation vector value;

a plurality of movement compensators for receiving the movement compensation vector value and outputting of the previous image memory and the next image memory, wherein the movement compensators are operated by a movement compensation selection signal to perform a half-pel, quarter-pel, or octa-pel movement compensation; and

a resizer for selecting one of the movement compensators based on the resizing control signal.

6. The video decoder as claimed in claim 1, wherein the resizing control unit determines the resizing control value based on a display size of the digital broadcast receiver.

7. The video decoder as claimed in claim 1, wherein the resizing control unit determines the resizing control value based on a display size of the digital broadcast receiver and an image scan type analyzed by the header analyzer.

8. The video decoder as claimed in claim 1, wherein the resizing control unit determines the resizing control value based on a display size of the digital broadcast receiver, and an image scan type and a block scan type analyzed by the header analyzer.

9. The video decoder as claimed in claim 1, wherein the resizing control unit determines the resizing control value based on a display size of the digital broadcast receiver, an image scan type and a block scan type analyzed by the header analyzer, and a decoding speed selected by a user.

10. The video decoder as claimed in claim 1, wherein the resizing control unit determines the resizing control value based on a display size of the digital broadcast receiver, an image scan type and a block scan type analyzed by the header analyzer, a decoding speed selected by a user, and a decoding speed of the digital broadcast receiver.

11. The video decoder as claimed in claim 1, wherein the inverse transform unit is an Inverse Integer Transform (IIT) unit.

12. The video decoder as claimed in claim 11, wherein the Inverse integer transform (IIT) unit comprises:

a Y axis resizer for selecting an N point inverse integer transformer using a Y axis control signal of the resizing control signal;

an N number of Y axis inverse integer transformers including the selected N point inverse integer transformer for inverse integer transforming Y axis video data in a resized area;

an X axis resizer for selecting an M point inverse integer transformer using an X axis control signal of the resizing control signal;

an M number of X axis inverse integer transformers including the selected M point inverse integer transformer for inverse integer transforming X axis video data in a resizing area, the X axis video data being stored in a Y buffer.

13. The video decoder as claimed in claim 12, wherein the variable length decoder comprises:

a resizer for resizing the separated video data based on the resizing control signal;

a table converter for decoding the received variable length coded video data into video data with the original size; and

a buffer for storing the video data decoded by the table converter,

wherein the resizer controls the table converter to decode data in blocks included in the resizing area set by the resizing control signal and controls the buffer to store the video data in the resizing area.

14. The video decoder as claimed in claim 13, wherein the movement compensator unit comprises:

a buffer for storing a received movement compensation vector value;

a previous image memory for storing a previous image in order to compare the movement compensation vector value;

a next image memory for storing a next image in order to compare the movement compensation vector value;

a plurality of movement compensators for receiving the movement compensation vector value and outputting of the previous image memory and the next image memory, wherein the movement compensators are operated by a movement compensation selection signal to perform one of a half-pel, quarter-pel, and octa-pel movement compensation; and

a resizer for selecting one of the movement compensators based on the resizing control signal.

15. The video decoder as claimed in claim 14, wherein the resizing control unit determines the resizing control value based on a display size of the digital broadcast receiver.

16. The video decoder as claimed in claim 14, wherein the resizing control unit determines the resizing control value based on a display size of the digital broadcast receiver and an image scan type analyzed by the header analyzer.

17. The video decoder as claimed in claim 14, wherein the resizing control unit determines the resizing control value based on a display size of the digital broadcast receiver, an image scan type and a block scan type analyzed by the header analyzer, and a decoding speed selected by a user.

18. The video decoder as claimed in claim 14, wherein the resizing control unit determines the resizing control value based on a display size of the digital broadcast receiver, an image scan type and a block scan type analyzed by the header analyzer, a decoding speed selected by a user, and a decoding speed of the digital broadcast receiver.

19. A video decoder of a digital broadcast receiver, comprising:

a resizing control unit for generating a resizing control signal for resizing received video data;

a header analyzer for analyzing header information from a decoded video stream and separating and outputting video data;

a variable length decoder for decoding the video data output from the header analyzer into an original pixel data with an original data size using a variable length table, the variable length decoder including a resizer, a table converter, and a buffer, the resizer controlling the table converter to decode data in blocks included in the resizing area set by the resizing control signal, and controlling the buffer to store the video data in the resizing area;

a dequantizer for dequantizing the decoded video data;

an Inverse Transform (IT) unit for resizing and converting the dequantized frequency-domain video data into a two dimensional spatial domain video data by the resizing control signal;

a movement compensator unit including movement compensators, one of which is selected by the resizing control signal, the selected movement compensator compensating for movement of a movement compensation data corresponding to one of the inverse-transformed video data and the separated video data; and

a color converter for converting outputs of the inverse transform unit and the movement compensation unit into display data.

20. The video decoder as claimed in claim 19, wherein the inverse transform unit comprises an Inverse Discrete Cosine Transform (IDCT) unit including at least one Y axis inverse discrete cosine transformer, at least one X axis inverse discrete cosine transformer,

wherein a corresponding Y axis inverse discrete cosine transformer and a corresponding X axis inverse discrete cosine transformer are operated by the resizing control signal to resize and inverse discrete cosine transform the variable length decoded video data.

21. The video decoder as claimed in claim 20, wherein the inverse transform unit comprises an Inverse Integer Transform (IIT) unit including at least one Y axis inverse integer transformer and at least one X axis inverse integer transformer,

wherein a corresponding Y axis inverse integer transformer and a corresponding X axis inverse integer transformer are operated by the resizing control signal to resize and inverse integer transform the variable length decoded video data.

22. A digital broadcast receiver comprising:

a control unit for generating a channel selection signal using a user selection and generating a resizing control signal for resizing received video data;

a tuner for selecting a channel of a received digital broadcast signal according to the channel selection signal;

a demodulator for demodulating the selected digital broadcast signal;

a decoder including a demultiplexer for separating an audio stream and a video stream from the demodulated digital broadcast signal, a video decoder for decoding data of the separated video stream, and an audio decoder for decoding data of the separated audio stream, the video decoder resizing a decoding area of the received video data based on the resizing control signal output from the control unit and decoding the video data in the resizing area;

a display unit for displaying the decoded video data; and

a memory for storing the digital broadcast signal output from the demodulator in a record mode, the memory including buffers for temporarily storing data processed by the decoder.

23. The digital broadcast receiver as claimed in claim 22, wherein the video decoder comprises:

a header analyzer for analyzing header information from the decoded video stream and for separating and outputting a video data;

a variable length decoder for resizing the separated video data based on the resizing control signal, and decoding the resized video data into a pixel data with an original pixel data size using a variable length table;

a dequantizer for dequantizing the decoded video data;

an Inverse Transform (IT) unit for resizing and converting the dequantized frequency-domain video data into a two dimensional spatial domain video data by the resizing control signal;

a movement compensator unit for compensating for movement of the pixel data by a predetermined pixel interval based on the resizing control signal;

an adder for adding outputs of the inverse transform unit and the movement compensator unit; and

a color converter for converting a video data output from the adder into display data for the display unit.

24. The digital broadcast receiver as claimed in claim 23, wherein the inverse transform unit comprises an Inverse Discrete Cosine Transform (IDCT) unit.

25. The digital broadcast receiver as claimed in claim 24, wherein the IDCT unit comprises:

a Y axis resizer for selecting an N point inverse discrete cosine transformer using a Y axis control signal of the resizing control signal;

an N number of Y axis inverse discrete cosine transformers including the selected N point inverse discrete cosine transformer for inverse cosine transforming Y axis video data in a resized area;

an X axis resizer for selecting an M point inverse discrete cosine transformer using an X axis control signal of the resizing control signal; and

an M number of X axis inverse discrete cosine transformers including the selected M point inverse discrete cosine transformer for inverse cosine transforming X axis video data in a resizing area, the X axis video data being stored in a Y buffer.

26. The digital broadcast receiver as claimed in claim 23, wherein the inverse transform unit comprises an Inverse Integer Transform (IIT) unit.

27. The digital broadcast receiver as claimed in claim 26, wherein the IIT unit comprises:

a Y axis resizer for selecting an N point inverse integer transformer using a Y axis control signal of the resizing control signal;

an N number of Y axis inverse integer transformers including the selected N point inverse integer transformer for inverse integer transforming Y axis video data in a resized area;

an X axis resizer for selecting an M point inverse integer transformer using an X axis control signal of the resizing control signal; and

an M number of X axis inverse integer transformers including the selected M point inverse integer transformer for inverse integer transforming X axis video data in a resizing area, the X axis video data being stored in a Y buffer.

28. The digital broadcast receiver as claimed in claim 23, wherein the variable length decoder comprises:

a table converter for decoding the received variable length coded video data into video data with the original size;

a buffer for storing the video data decoded by the table converter; and

a resizer for controlling the table converter to decode pixel data included in a predetermined resizing area set by the resizing control signal and controlling the buffer to store the video data in the resizing area.

29. The digital broadcast receiver as claimed in claim 23, wherein the movement compensator unit comprises:

a buffer for storing a received movement compensation vector value;

a previous image memory for storing a previous image in order to compare the movement compensation vector value;

a next image memory for storing a next image in order to compare the movement compensation vector value;

a plurality of movement compensators for receiving the movement compensation vector value and outputting of the previous image memory and the next image memory, wherein the movement compensators are operated by a movement compensation selection signal to perform one of a half-pel, quarter-pel, and octa-pel movement compensation; and

a resizer for selecting one of the movement compensators based on the resizing control signal.

30. The digital broadcast receiver as claimed in claim 23, wherein the control unit determines the resizing control value based on a display size of the digital broadcast receiver.

31. The digital broadcast receiver as claimed in claim 23, wherein the control unit determines the resizing control value based on a display size of the digital broadcast receiver and an image scan type analyzed by the header analyzer.

32. The digital broadcast receiver as claimed in claim 23, wherein the control unit determines the resizing control value based on a display size of the digital broadcast receiver, an image scan type and a block scan type analyzed by the header analyzer, a decoding speed selected by a user, and a decoding speed of the digital broadcast receiver.

33. A digital broadcast receiver of a portable terminal that includes an RF communication unit for up-converting a transmitted signal to a signal of an RF band and down-converting a received RF signal into a baseband signal and a data processor for demodulating and the decoding the baseband signal, the digital broadcast receiver comprising:

a control unit for generating a channel selection signal by a user selection and generating a resizing control signal for resizing a received video data based on a display size of the portable terminal;

a tuner for selecting a channel of a received digital broadcast signal according to channel selection signal generated by the control unit;

a demodulator for demodulating the selected digital broadcast signal;

a decoder including a demultiplexer for separating an audio stream and a video stream from the demodulated digital broadcast signal, a video decoder for decoding data of the separated video stream, and an audio decoder for decoding data of the separated audio stream, the video decoder resizing a decoding area of the received video data based on the resizing control signal output from the control unit and decoding the video data in the resizing area;

a display unit for displaying the decoded video data; and

a memory for storing the digital broadcast signal output from the demodulator in a record mode,

wherein the memory includes buffers for temporarily storing data processed by the decoder.

34. The digital broadcast receiver as claimed in claim 33, wherein the video decoder comprises:

a header analyzer for analyzing header information from the decoded video stream and separating and outputting video data;

a variable length decoder for decoding the video data output from the header analyzer into an original pixel data with an original data size by using a variable length table, the variable length decoder including a resizer, a table converter, and a buffer, the resizer controlling the table converter to decode data in blocks included in the resizing area set by the resizing control signal and controlling the buffer to store the video data in the resizing area;

a dequantizer for dequantizing the decoded video data;

an Inverse Transform (IT) unit for resizing and converting the dequantized frequency-domain video data into two dimensional spatial domain video data by the resizing control signal;

a movement compensator unit including movement compensators, one of which is selected by the resizing control signal, the selected movement compensator compensating for movement of a movement compensation data corresponding to one of the inverse-transformed video data and the separated video data; and

a color converter for converting outputs of the inverse transform unit and the movement compensator unit into display data.

35. The digital broadcast receiver as claimed in claim 34, wherein the inverse transform unit is an Inverse Discrete Cosine Transform (IDCT) unit, comprising:

a Y axis resizer for selecting an N point inverse discrete cosine transformer using a Y axis control signal of the resizing control signal;

an N number of Y axis inverse discrete cosine transformers including the selected N point inverse discrete cosine transformer for inverse cosine transforming Y axis video data in a resized area;

an X axis resizer for selecting an M point inverse discrete cosine transformer using an X axis control signal of the resizing control signal; and

an M number of X axis inverse discrete cosine transformers including the selected M point inverse discrete cosine transformer for inverse cosine transforming X axis video data in a resizing area, the X axis video data being stored in a Y buffer.

36. The digital broadcast receiver as claimed in claim 34, wherein the inverse transform unit is an Inverse Integer Transform (IIT) unit comprising:

a Y axis resizer for selecting an N point inverse integer transformer using a Y axis control signal of the resizing control signal;

an N number of Y axis inverse integer transformers including the selected N point inverse integer transformer for inverse integer transforming Y axis video data in a resized area;

an X axis resizer for selecting an M point inverse integer transformer using an X axis control signal of the resizing control signal; and

an M number of X axis inverse integer transformers including the selected M point inverse integer transformer for inverse integer transforming X axis video data in a resizing area, the X axis video data being stored in a Y buffer.

37. The digital broadcast receiver as claimed in claim 34, wherein the variable length decoder comprises:

a table converter for decoding the received variable length coded video data into video data with the original size;

a buffer for storing the video data decoded by the table converter; and

a resizer for controlling the table converter to decode pixel data included in a predetermined resizing area set by the resizing control signal and controlling the buffer to store the video data in the resizing area.

38. The digital broadcast receiver as claimed in claim 34, wherein the movement compensator unit comprises:

a buffer for storing a received movement compensation vector value;

a previous image memory for storing a previous image in order to compare the movement compensation vector value;

a next image memory for storing a next image in order to compare the movement compensation vector value;

a plurality of movement compensators for receiving the movement compensation vector value and outputting of the previous image memory and the next image memory, wherein the movement compensators are operated by a movement compensation selection signal to perform one of a half-pel, quarter-pel, and octa-pel movement compensation; and

a resizer for selecting one of the movement compensators based on the resizing control signal.

39. The digital broadcast receiver as claimed in claim 34, wherein the control unit determines the resizing control value based on a display size of the digital broadcast receiver.

40. The digital broadcast receiver as claimed in claim 34, wherein the control unit determines the resizing control value based on a display size of the digital broadcast receiver and an image scan type analyzed by the header analyzer.

41. The digital broadcast receiver as claimed in claim 34, wherein the control unit determines the resizing control value based on a display size of the digital broadcast receiver, an image scan type and a block scan type analyzed by the header analyzer, a decoding speed selected by a user, and a decoding speed of the digital broadcast receiver.

42. A method for decoding a coded video data in a digital broadcast receiver, the method comprising the steps of:

determining a resizing control signal for resizing a received video data;

analyzing header information from a decoded video stream;

separating and outputting a video data;

resizing the separated video data using the resizing control signal;

decoding the resized video data into an original pixel data with an original data size using a variable length table;

dequantizing the decoded video data;

resizing and converting the dequantized frequency-domain video data into two dimensional spatial domain video data by the resizing control signal;

movement compensating for movement of a movement compensation data corresponding to one of the inverse-transformed video data and the separated video data; and

converting the two dimensional spatial domain video data and the movement compensated data into display data for a display unit.

43. The method as claimed in claim 42, wherein a scan area is setup for a Y matrix by the resizing control signal, and data of the setup scan area is inverse discrete cosine transformed.

44. The method as claimed in claim 42, wherein a scan area is setup for a Y matrix by the resizing control signal, and data of the setup scan area is inverse integer transformed.

45. The method as claimed in claim 42, wherein the steps of resizing and decoding the resized video data comprise the steps of:

decoding the received variable length coded video data into a video data with the original size;

storing the decoded data;

interrupting decoding of other data until all pixel data included in a predetermined resizing area set by the resizing control signal is decoded; and

outputting the decoded video data in the resizing area from among the stored decoded data.

46. The method as claimed in claim 42, wherein the step movement compensating comprises the steps of:

storing a received movement compensation vector value, a previous image, and a next image, in order to compare the movement compensation vector value; and

performing movement compensation for the movement compensation vector value, the previous image, and the next image by a movement compensator selected based on the resizing control signal.

47. The method as claimed in claim 42, wherein a signal capable of selecting an area including pixel data with a size corresponding to the display size of the display unit is determined as the resizing control signal.

48. The method as claimed in claim 42, wherein the resizing control signal is determined based on a display size of the digital broadcast receiver, an image scan type and a block scan type included in header information, a decoding speed selected by a user, and a decoding speed of the digital broadcast receiver.

49. A method for processing an image in a digital broadcast receiver, the method comprising the steps of:

generating a channel selection signal according to a user selection;

generating a resizing control signal for resizing a received video data;

selecting a channel of a received digital broadcast signal by channel selection of the control unit;

demodulating the selected digital broadcast signal;

separating an audio stream and a video stream from the decoded digital broadcast signal;

decoding data of the separated audio stream and video stream; and

reproducing and displaying the decoded video and audio data, wherein a decoding area for the video data is resized based on the resizing control signal and the video data in the resized area is then decoded.

50. A method for processing a broadcast signal of a portable terminal having a wireless communication unit for wireless communication, the method comprising the steps of:

generating a channel selection signal according to a user selection;

generating a resizing control signal for resizing a received digital broadcast signal based on a display size of the portable terminal;

selecting a channel of a received digital broadcast signal by channel selection of the control unit;

demodulating the selected digital broadcast signal;

separating an audio stream and a video stream from the decoded digital broadcast signal;

decoding data of the separated audio stream and video stream; and

reproducing and displaying the decoded video and audio data,

wherein a decoding area for the video data is resized based on the resizing control signal and the video data in the resized area is then decoded.