Transcoding apparatus and method between two codecs each including a deblocking filter

1. A transcoding method between first and second codecs each comprising a deblocking filter, the transcoding method comprising:

decoding input data encoded according to the first codec, according to the first codec so as to generate decoded data; and

encoding the decoded data according to the second codec,

wherein the decoded data comprises

first data on which deblocking filtering is not performed by the first codec, the first data stored in a first image buffer before being processed by the second codec, and

second data, to be used for prediction, on which deblocking filtering is performed by the first codec, the second data stored in a second image buffer before being processed by the second codec.

2. The transcoding method of claim 1 , wherein the first data is used as input data when the second codec performs encoding and when the second codec performs motion estimation.

3. The transcoding method of claim 1 , wherein the first data is used as input data when the second codec performs encoding, and

wherein the second data is used as input data when the second codec performs motion estimation.

4. The transcoding method of claim 1 , wherein each of the first and second codecs is one of a baseline profile of an H.264/Advanced Video Coding (AVC) codec, a main profile of the H.264/AVC codec, an extended profile of the H.264/AVC codec, a scalable video coding (SVC) codec, a multiview video coding (MVC) codec, a VC-1 codec of the Society of Motion Picture and Television Engineers (SMPTE), and an Audio Video Standard (AVC) codec.

5. A transcoding method between first and second codecs each comprising a deblocking filter, the transcoding method comprising:

decoding input data encoded according to the first codec, according to the first codec so as to generate decoded data; and

encoding the decoded data according to the second codec,

wherein the decoded data comprises

first data on which deblocking filtering is adaptively performed by the first codec, the first data stored in a first image buffer before being processed by the second codec, and

second data, to be used for prediction, on which deblocking filtering is not performed by the first codec, the second data stored in a second image buffer before being processed by the second codec.

6. The transcoding method of claim 5 , wherein the first data is used as input data when the second codec performs encoding and when the second codec performs motion estimation.

7. The transcoding method of claim 6 , wherein the first data is generated by performing deblocking filtering according to the first codec on only some block boundaries based on types of the block boundaries, or by performing deblocking filtering according to the first codec by using a different boundary strength from the first codec.

8. The transcoding method of claim 7 , wherein the types of the block boundaries are determined by using a first block unit which is a transformation unit of the first codec, and a second block unit which is a transformation unit of the second codec, and

wherein the first data is data in which deblocking filtering is performed on an area corresponding to block boundaries in the first block unit and not corresponding to block boundaries in the second block unit, and is not performed on an area corresponding to block boundaries in both the first block unit and the second block unit.

9. The transcoding method of claim 8 , wherein the first data is used as input data when the second codec performs encoding, and

wherein the second data is used as input data when the second codec performs motion estimation.

10. A transcoding apparatus between first and second codecs each comprising a deblocking filter, the transcoding apparatus comprising:

a decoding unit for decoding input data encoded according to the first codec and outputting decoded data;

a first image buffer for storing the first decoded data as a first data before filtering by a deblocking filter of the decoding unit;

a second image buffer for storing the decoded data as a second data after filtering by the deblocking filter of the decoding unit; and

an encoding unit for encoding the first data input from the first image buffer, according to the second codec.

11. The transcoding apparatus of claim 10 , wherein the first data is used as input data when the encoding unit performs encoding and when the encoding unit performs motion estimation.

12. The transcoding apparatus of claim 10 ,

wherein the encoding unit encodes the first data according to the second codec together with the second data input from the second image buffer.

13. The transcoding apparatus of claim 12 , wherein the first data is used as input data when the encoding unit performs encoding, and

wherein the second data is used as input data when the encoding unit performs motion estimation.

14. A transcoding apparatus between first and second codecs each comprising a deblocking filter, the transcoding apparatus comprising:

a decoding unit for decoding input data encoded according to the first codec, according to the first codec;

an adaptive deblocking filter for performing adaptive deblocking filtering on decoded data;

a first image buffer for storing the decoded data as a first data when the decoded data are filtered by the adaptive deblocking filter;

a second image buffer for storing the decoded data as a second data when the decoded data are not filtered by the adaptive deblocking filter; and

an encoding unit for encoding the first data input from the first image buffer, according to the second codec.

15. The transcoding apparatus of claim 14 , wherein the first data is used as input data when the encoding unit performs encoding and when the encoding unit performs motion estimation.

16. The transcoding apparatus of claim 15 , wherein the adaptive deblocking filter performs deblocking filtering according to the first codec on only some block boundaries based on types of the block boundaries, or performs deblocking filtering according to the first codec by using a different boundary strength from the first codec.

17. The transcoding apparatus of claim 14 , wherein the adaptive deblocking filter comprises:

a second deblocking filter for performing deblocking filtering according to the first codec; and

a deblocking filter control unit for controlling operations of the second deblocking filter.

18. The transcoding apparatus of claim 14 , wherein the encoding unit encodes the first data according to the second codec together with the second data input from the second image buffer.