Source: https://patents.google.com/patent/US8412363B2/en
Timestamp: 2019-01-17 06:18:00
Document Index: 446640456

Matched Legal Cases: ['Application No. 2', 'Application No. 04776572', 'Application No. 05780308', 'Application No. 05780308', 'Application No. 05780308', 'Application No. 2005270105', 'Application No. 2011203047', 'Application No. 2005270105', 'Application No. 2010200873', 'Application No. 200580026107', 'Application No. 201010501205', 'Application No. 201010501205', 'Application No. 200580026107', 'Application No. 93117000']

US8412363B2 - Methods and apparatus for mixing compressed digital bit streams - Google Patents
Methods and apparatus for mixing compressed digital bit streams Download PDF
US8412363B2
US8412363B2 US11571483 US57148305A US8412363B2 US 8412363 B2 US8412363 B2 US 8412363B2 US 11571483 US11571483 US 11571483 US 57148305 A US57148305 A US 57148305A US 8412363 B2 US8412363 B2 US 8412363B2
US11571483
US20080253440A1 (en )
G11B2020/00028—Advanced audio coding [AAC]
G11B2020/00036—AC-3, i.e. ATSC digital audio compression standard
This patent arises from the U.S. national stage of International Patent Application No. PCT/US2005/023578, entitled “Methods and Apparatus for Mixing Compressed Digital Bit Streams,” filed on Jun. 29, 2005. Additionally, this patent claims priority from U.S. Provisional Application Ser. No. 60/585,115, entitled “Mixing System and Method for Compressed Bit Streams,” filed on Jul. 2, 2004, and U.S. Provisional Application Ser. No. 60/586,354, entitled “Mixing System and Method for Compressed Bit Streams,” filed on Jul. 8, 2004. This patent is also related to International Patent Application No. PCT/US04/18953, entitled “Methods and Apparatus for Embedding Watermarks,” filed on Jun. 14, 2004. International Patent Application No. PCT/US2005/023578, U.S. Provisional Application Ser. No. 60/585,115, U.S. Provisional Application Ser. No. 60/586,354, and International Patent Application No. PCT/US04/18953 are hereby incorporated by reference in their entireties.
FIG. 3 illustrates the format 300 of an example single-channel compressed digital bit stream to be processed as the compressed main digital bit stream 220 by the example mixing device 200 of FIG. 2. The format 300 is based on an uncompressed digital bit stream which includes a plurality of 256-sample time-domain audio blocks 310, generally shown as A0, A1, A2, A3, A4, and A5. The MDCT algorithm processes the audio blocks 310 to generate MDCT coefficient sets 320, shown by way of example as MA0, MA1, MA2, MA3, MA4, and MA5 (where MA5 is not shown). For example, the MDCT algorithm may process the audio blocks A0 and A1 to generate the MDCT coefficient set MA0. The audio blocks A0 and A1 are concatenated to generate a 512-sample audio block (e.g., an AC-3 long block) that is MDCT transformed using the MDCT algorithm to generate the MDCT coefficient set MAO containing 256 MDCT coefficients. Similarly, the audio blocks A1 and A2 may be processed to generate the MDCT coefficient set MA1. Thus, the audio block A1 is an overlapping audio block because it is used to generate both MDCT coefficient sets MA0 and MA1. In a similar manner, the MDCT algorithm is used to transform the audio blocks A2 and A3 to generate the MDCT coefficient set MA2, the audio blocks A3 and A4 to generate the MDCT coefficient set MA3, the audio blocks A4 and A5 to generate the MDCT coefficient set MA4, etc. Thus, the audio block A2 is an overlapping audio block used to generate the MDCT coefficient sets MA1 and MA2, the audio block A3 is an overlapping audio block used to generate the MDCT coefficient sets MA2 and MA3, the audio block A4 is an overlapping audio block used to generate the MDCT coefficient sets MA3 and MA4, etc. Together, the MDCT coefficient sets 320 are packed to form the compressed digital bit stream 220 of FIG. 2.
The acquisition unit 410 is configured to acquire one or more frames 510 (shown in FIG. 5) associated with the compressed digital bit stream 220 (shown in FIG. 2), a portion of which is shown by way of example as Frame A and Frame B in FIG. 5. As mentioned previously, the compressed digital bit stream 220 may be a digital bit stream compressed in accordance with the AC-3 standard (hereinafter referred to as the “AC-3 data stream” 220). While the AC-3 data stream 220 may include multiple channels, for purposes of clarity, the following example describes the AC-3 data stream 220 as including only one channel. In the AC-3 data stream 220, each of the frames 510 includes a plurality of original MDCT coefficient sets 520. In accordance with the AC-3 compression standard, for example, each of the frames 510 includes six original MDCT coefficient sets (i.e., six “audblks”, wherein each MDCT coefficient set corresponds to an AC-3 audblk). For example, Frame A includes the original MDCT coefficient sets MAO, MA1, MA2, MA3, MA4 and MA5 and Frame B includes the original MDCT coefficient sets MB0, MB1, MB2, MB3, MB4 and MB5.
As described in detail in the AC-3 compression standard, a mantissa and an exponent are used to represent each original MDCT coefficient. The AC-3 compression standard employs techniques to reduce the number of bits used to represent each original MDCT coefficient. Psycho-acoustic masking is one factor that may be utilized by these techniques. For example, the presence of audio energy Ek either at a particular frequency k (e.g., a tone) or spread across a band of frequencies proximate to the particular frequency k (e.g., a noise-like characteristic) creates a masking effect. That is, the human ear is unable to perceive a change in energy in a spectral region either at a frequency k or spread across the band of frequencies proximate to the frequency k if that change is less than a given energy threshold ΔEk. Because of this characteristic of the human ear, an MDCT coefficient mk associated with the frequency k may be quantized with a step size related to ΔEk without risk of causing any perceptible changes to the audio content. For the AC-3 data stream 220, each original MDCT coefficient mk is represented as a mantissa Mk and an exponent Xk such that mk=Mk0.2−X k, where 2−X k represents the quantization step size for the coefficient mk. The number of bits used to represent the mantissa Mk of each original MDCT coefficient of the original MDCT coefficient sets 520 may be determined based on known quantization look-up tables published in the AC-3 compression standard, such as the example quantization look-up table 600 of FIG. 6. In the example of FIG. 6, the quantization look-up table 600 provides mantissa codes or bit patterns and corresponding mantissa values for MDCT coefficients represented by a four-bit number. As described in detail below, the mantissa Mk may be modified to represent an MDCT coefficient resulting from mixing the uncompressed auxiliary digital bit stream 210 with the AC-3 data stream 220.
Returning to FIGS. 4 and 5, the modification unit 430 is configured to perform an inverse transform of each of the original MDCT coefficient sets 520 to generate time-domain audio blocks 530, shown by way of example as TA0′, . . . , TA3″, TA4′, TA4″, TA5′, TA5″, TB0′, TB0″, TB1′, TB1″, . . . , and TB5′ (TA0″ through TA3′ and TB2′ through TB4″ are not shown). The modification unit 430 performs inverse transform operations to generate sets of previous (old) time-domain audio blocks (which are represented as prime blocks) and sets of current (new) time-domain audio blocks (which are represented as double-prime blocks) associated with the 256-sample time-domain audio blocks that were concatenated to form the original MDCT coefficient sets 520 of the AC-3 data stream 220. For example, the modification unit 430 performs an inverse transform on the original MDCT coefficient set MA5 to generate time-domain blocks TA4″ and TA5′, the original MDCT coefficient set MB0 to generate TA5″ and TB0′, the original MDCT coefficient set MB1 to generate TB0″ and TB1′, etc. Then, the modification unit 430 generates reconstructed time-domain audio blocks 540, which provide a reconstruction of the original time-domain audio blocks that were compressed to form the AC-3 data stream 220. To generate the reconstructed time-domain audio blocks 540, the modification unit 430 may add time-domain audio blocks 530 based on, for example, the known Princen-Bradley time domain alias cancellation (TDAC) technique as described in Princen et al., Analysis/Synthesis Filter Bank Design Based on Time Domain Aliasing Cancellation, Institute of Electrical and Electronics Engineers (IEEE) Transactions on Acoustics, Speech and Signal Processing, Vol. ASSP-35, No. 5, pp. 1153-1161 (1986), which is incorporated herein by reference in its entirety. For example, the modification unit 430 may reconstruct the time-domain audio block A5 of FIG. 3 (corresponding to TA5R) by adding the prime time-domain audio block TA5′ and the double-prime time-domain audio block TA5″ using the Princen-Bradley TDAC technique. Likewise, the modification unit 430 may reconstruct the time-domain audio block BO (corresponding to TB0R) by adding the prime audio block TB0′ and the double-prime audio block TB0″ using the Princen-Bradley TDAC technique. In this manner, the original time-domain audio blocks used to form the AC-3 data stream 220 are reconstructed to enable the uncompressed auxiliary digital bit stream 210 to be mixed directly into the AC-3 data stream 220.
The difference between the original MDCT coefficient sets 520 and the intermediate mixed MDCT coefficient sets 560 represents a change in the AC-3 data stream 220 corresponding to mixing the uncompressed auxiliary digital bit stream 210 with the AC-3 data stream 220. Thus, it is possible to generate the output mixed MDCT coefficient sets 570, shown by way of example as MA0X, . . . , MA4X, MA5X, MB0X, . . . and MB5X (blocks MA1X, MA2X, MA3X, MB1X, MB2X, MB3X and MB4X are not shown), based on the format of the original MDCT coefficient sets 520 and, thus, the compression associated with the original MDCT coefficient sets 520. For example, in connection with FIG. 6, the modification unit 430 may represent the mixed MDCT coefficient set MA5X in a mantissa and exponent format using the exponents associated with the corresponding original MDCT coefficient set MA5 and mantissas based on the corresponding intermediate mixed MDCT coefficient set MA5I. Furthermore, quantization look-up tables (e.g., the look-up table 600 of FIG. 6) corresponding to the original MDCT coefficient sets 520 may be used to quantize the mantissa values of the intermediate mixed MDCT coefficient 560 to generate the mantissa values for the MDCT coefficients of the mixed MDCT coefficient sets 570. A person of ordinary skill in the art will recognize that the resulting quantized mixed mantissa values represent the change in or augmentation of the AC-3 data stream 220 as a result of mixing in the uncompressed auxiliary digital bit stream 210. In this example implementation, the exponents of the original MDCT coefficients are used to generate the corresponding mixed MDCT coefficients of the mixed MDCT coefficient sets 570. Changing the exponents might require that the underlying compressed signal representation be recomputed, thereby requiring the compressed signal to undergo a true decompression/compression cycle. To avoid a decompression/compression cycle, if a modification of only the mantissa is insufficient to fully represent the difference between a mixed and an original MDCT coefficient, the affected MDCT mantissa is set to a maximum or minimum value, as appropriate.
To mix the uncompressed auxiliary bit stream 210 with the AC-3 data stream 220, the modification unit 430 may represent the mixed MDCT coefficient set MA5X as a modification of the original MDCT coefficients in the original MDCT coefficient set MA5. Continuing with the above example, either mantissa code 0011 or mantissa code 0100 may replace the mantissa code 0101 associated with the MDCT coefficient mk to represent the mixed MDCT coefficient xmk because the intermediate mixed mantissa associated with the corresponding mixed MDCT coefficient xmk lies between the mantissa codes of 0011 and 0100 (because the intermediate mantissa value corresponding to the mixed MDCT coefficient xmk is −0.4300). The mantissa value corresponding to the mantissa code 0011 is −0.5333 (i.e., −8/15) and the mantissa value corresponding to the mantissa code 0100 is −0.4 (i.e., −6/15). In this example, the modification unit 430 selects the mantissa code 0100 to represent the mixed MDCT coefficient XMk because the mantissa value −0.4 corresponding to the mantissa code 0100 is closest to the desired intermediate mixed mantissa value −0.4300. As a result, the new mantissa bit pattern of 0100, which corresponds to the mixed mantissa XMk of the mixed MDCT coefficient XMk, replaces the original mantissa bit pattern of 0101. Likewise, each of the original MDCT coefficients in the original MDCT coefficient set MA5 may be modified in the manner described above to generate the corresponding mixed MDCT coefficient in the mixed MDCT coefficient set MA5X. Furthermore, if an intermediate mixed mantissa value is outside the quantization range of mantissa values (i.e., greater than 0.9333 or less than −0.9333), either the positive limit of 1110 or the negative limit of 0000 is selected as the output mixed mantissa code, as appropriate. Additionally, and as discussed above, while the mantissa codes associated with each original MDCT coefficient of an original MDCT coefficient set may be modified as described above, the exponents associated with the original MDCT coefficients remain unchanged in the generation of the corresponding mixed MDCT coefficient.
For simplicity, the AC-3 data stream 220 is described in connection with FIG. 5 to include a single channel. However, the methods and apparatus disclosed herein may be applied to compressed digital data streams having audio blocks associated with multiple channels, such as 5.1 channel audio (i.e., five full-bandwidth channels and one low frequency effects channel), as described below in connection with FIGS. 7 and 8. In the example of FIG. 7, an uncompressed digital bit stream format 700 may include a plurality of audio block sets 710. Each of the audio block sets 710 may include audio blocks associated with multiple channels 720 and 730 including, for example, a front left channel, a center channel, a front right channel, a rear left channel, a rear right channel, and a low-frequency effect (LFE) channel (e.g., a sub-woofer channel). For example, the audio block set AUD0 includes an audio block A0L associated with the front left channel, an audio block A0C associated with the center channel, an audio block A0R associated with the front right channel, an audio block A0RL associated with the rear left channel, an audio block A0RR associated with the rear right channel, and an audio block A0LFE associated with the LFE channel. Similarly, the audio block set AUD1 includes an audio block A1L associated with the front left channel, an audio block A1C associated with the center channel, an audio block AIR associated with the front right channel, an audio block A1RL associated with the rear left channel, an audio block A1RR associated with the rear right channel, and an audio block A1LFE associated with the LFE channel.
As illustrated in FIG. 10, the modification process 940 begins at block 1010 at which the modifying unit 430 performs an inverse transform of the original MDCT coefficient sets 520 to generate inverse transformed time-domain audio blocks, such as the time-domain audio blocks 530. In particular, the modification unit 430 generates a previous (old) time-domain audio block (which, for example, is represented as a prime block in FIG. 5) and a current (new) time-domain audio block (which is represented as a double-prime block in FIG. 5) associated with each of the 256-sample original time-domain audio blocks 530 used to generate the corresponding original MDCT coefficient set. As described above in connection with FIG. 5, for example, the modification unit 430 may generate TA4″ and TA5′ from the MDCT coefficient set MA5, TA5″ and TB0′ from the MDCT coefficient set MB0, and TB0″ and TB1′ from the MDCT coefficient set MB1. Control then proceeds to block 1020 at which the modification unit 430 adds corresponding old and new blocks to reconstruct time-domain audio blocks based on, for example, the Princen-Bradley TDAC technique to generate reconstructed time-domain audio blocks, such as the reconstructed time-domain audio block 540 of FIG. 5. Following the above example, the old block TA5′ and the new block TA5″ may be added to reconstruct the time-domain audio block A5 (i.e., the reconstructed time-domain audio block TA5R) while the prime block TB0′ and the double-prime block TB0″ may be added to reconstruct the time-domain audio block BO (i.e., the reconstructed time-domain audio block TB0R).
To better understand the processing performed by the example process 1300 of FIG. 13, consider an example operation in which an AAS MDCT coefficient at block 1328 is represented with 4 bits, resulting in a 15-level quantization of the mantissa in the range −1.0 to 1.0. Suppose for purposes of this example that the AAS MDCT coefficient has an original mantissa value of 4.0/15=−0.2666. Then, according to the example AC-3 quantization look-up table 600 shown in FIG. 6, the bit pattern corresponding to the original AAS mantissa is 0101 (decimal 5). Next, assume for purposes of this example that the attenuated MAS mantissa value determined at block 1378 is equal to −0.1634. This attenuated MAS mantissa value causes a corresponding change to the AAS mantissa, resulting in an intermediate (raw) modified AAS mantissa value equal to −0.4300 being determined at block 1328, which lies between the quantization values of −8/15=−0.5333 and −6/15=−0.4 in the quantization look-up table 600. The value −6/15 is closest to the intermediate modified AAS mantissa value of −0.4300 and, thus, at block 1328 the bit pattern 0100 (decimal 4) is selected to replace the original code used to represent the original AAS mantissa to generate the resulting mixed MDCT coefficient
1. A method of mixing a first compressed digital bit stream with a second digital bit stream, the method comprising:
acquiring a frame associated with the first compressed digital bit stream;
unpacking the frame to obtain a plurality of original transform coefficient sets; and
modifying the plurality of original transform coefficient sets to mix the second digital bit stream with the first compressed digital bit stream, wherein modifying the plurality of original transform coefficient sets comprises:
determining a first mantissa code associated with a mixed transform coefficient of one of a plurality of mixed transform coefficient sets; and
substituting the first mantissa code associated with the mixed transform coefficient for a second mantissa code associated with a corresponding original transform coefficient of one of the plurality of original transform coefficient sets.
2. A method as defined in claim 1 wherein determining the first mantissa code associated with the mixed transform coefficient of the one of the plurality of mixed transform coefficient sets comprises:
determining a quantization step size associated with the corresponding original transform coefficient of one of the plurality of original transform coefficient sets;
generating the mixed transform coefficient based on combining an element associated with the first compressed digital bit stream and an element associated with the second digital bit stream;
quantizing the mixed transform coefficient based on the quantization step size to generate a quantized mantissa; and
determining the first mantissa code associated with the mixed transform coefficient based on the quantized mantissa.
3. A method as defined in claim 2 wherein the quantization step size is based on an exponent associated with the corresponding original transform coefficient.
4. A method as defined in claim 2 wherein combining the element associated with the first compressed digital bit stream and the element associated with the second digital bit stream comprises adding the element associated with the first compressed digital bit stream and the element associated with the second digital bit stream.
5. A method as defined in claim 4 further comprising attenuating at least one of the element of the first compressed digital bit stream or the element of the second digital bit stream prior to adding the element of the first compressed digital bit stream and the element of the second digital bit stream.
6. A method as defined in claim 1 wherein modifying the plurality of original transform coefficient sets comprises:
generating a plurality of time-domain audio blocks based on the plurality of original transform coefficient sets;
generating a plurality of mixed audio blocks based on the plurality of reconstructed audio blocks and the second digital bit stream.
7. A method as defined in claim 6 wherein generating the plurality of reconstructed audio blocks based on the plurality of time-domain audio blocks comprises generating a reconstructed time-domain audio block based on a first time-domain audio block and a second time-domain audio block.
8. A method as defined in claim 7 wherein generating the reconstructed time-domain audio block based on the first time-domain audio block and the second time-domain audio block comprises adding the first and second time-domain audio blocks.
9. A method as defined in claim 1 further comprising generating the plurality of mixed coefficient sets by determining mantissa codes associated with mixed transform coefficients of each of the plurality mixed transform coefficient sets based on compression information associated with the first compressed digital bit stream.
10. A method as defined in claim 1 wherein each of the plurality of original transform coefficient sets comprises one or more modified discrete cosine transform coefficients.
11. A method as defined in claim 1 wherein the first compressed digital bit stream is compressed in accordance with an audio compression standard.
12. A method as defined in claim 1 wherein acquiring the frame associated with the first compressed digital bit stream comprises acquiring audio blocks associated with at least one of a plurality of audio channels.
13. A method as defined in claim 1 wherein unpacking the frame to obtain the plurality of original transform coefficient sets comprises determining compression information associated with the first compressed digital bit stream.
14. A method as defined in claim 1 further comprising repacking the frame based on a plurality of mixed transform coefficient sets.
15. A method as defined in claim 1 wherein the first compressed digital bit stream corresponds to a main audio service and the second digital bit stream corresponds to an auxiliary audio service.
16. A method as defined in claim 1 wherein the second digital bit stream is compressed.
17. A method as defined in claim 16 wherein a pseudo-noise signal is added to the second digital bit stream prior to compression.
18. A method of mixing a first compressed digital bit stream with a second digital bit stream, the method comprising:
modifying the plurality of original transform coefficient sets to mix the second digital bit stream with the first compressed digital bit stream, wherein the second digital bit stream is compressed, a pseudo-noise signal is added to the second digital bit stream prior to compression, and modifying the plurality of original transform coefficient sets comprises:
determining a first mantissa code associated with a pseudo-noise transform coefficient of one of a plurality of pseudo-noise transform coefficient sets; and
modifying a second mantissa code associated with a corresponding original transform coefficient of one of the plurality of original transform coefficient sets based on the first mantissa code.
19. A method as defined in claim 18 wherein the plurality of pseudo-noise transform coefficient sets are determined based on an average spectral characteristic of the pseudo-noise signal.
20. A data stream mixing apparatus comprising:
an acquisition unit to acquire a frame associated with a first compressed digital data stream;
an unpacking unit to unpack the frame to obtain a plurality of original transform coefficient sets; and
a modification unit comprising a processor to modify the plurality of original transform coefficient sets to mix a second digital data stream with the first compressed digital data stream, wherein the modification unit is to:
determine a first mantissa code associated with a mixed transform coefficient of one of a plurality of mixed transform coefficient sets; and
substitute the first mantissa code associated with the mixed transform coefficient for a second mantissa code associated with a corresponding original transform coefficient of one of the plurality of transform coefficient sets.
21. An apparatus as defined in claim 20 wherein the modification unit is to:
determine a quantization step size associated with the corresponding original transform coefficient of one of the plurality of original transform coefficient sets;
generate the mixed transform coefficient based on a combination of an element associated with the first compressed digital data stream and an element associated with the second digital data stream;
quantize the mixed transform coefficient based on the quantization step size to generate a quantized mantissa; and
determine the first mantissa code associated with the mixed transform coefficient based on the quantized mantissa.
22. An apparatus as defined in claim 21 wherein the quantization step size is based on an exponent associated with the corresponding original transform coefficient.
23. An apparatus as defined in claim 21 wherein the combination of the element associated with the first compressed digital data stream and the element associated with the second digital data stream comprises the addition of the element associated with the first compressed digital data stream and the element associated with the second digital data stream.
24. An apparatus as defined in claim 23 wherein the combination of the element associated with the first compressed digital data stream and the element associated with the second digital data stream further comprises the attenuation of at least one of the element associated with the first compressed digital data stream or the element associated with the second digital data stream prior to the addition of the element associated with the first compressed digital data stream and the element associated with the second digital data stream.
25. An apparatus as defined in claim 20 wherein the modification unit is to:
generate a plurality of time-domain audio blocks based on the original transform coefficient sets;
generate a plurality of reconstructed audio blocks based on the plurality of time-domain audio blocks; and
generate a plurality of mixed audio blocks based on the plurality of reconstructed audio blocks and the second digital data stream.
26. An apparatus as defined in claim 25 wherein the modification unit is to generate a reconstructed time-domain audio block in the plurality of reconstructed audio blocks based on a first time-domain audio block and a second time-domain audio block in the plurality of time-domain audio blocks.
27. An apparatus as defined in claim 26 wherein the modification unit is to add the first and second time-domain audio blocks to generate the reconstructed time-domain audio block.
28. An apparatus as defined in claim 20 wherein the modification unit is further to generate the plurality of mixed transform coefficient sets based on the second digital data stream and compression information associated with the first compressed digital data stream.
29. An apparatus as defined in claim 20 wherein each of the plurality of original transform coefficient sets comprises one or more modified discrete cosine transform coefficients.
30. An apparatus as defined in claim 20 wherein the first compressed digital data stream is compressed in accordance with an audio compression standard.
31. An apparatus as defined in claim 20 wherein the acquisition unit is to acquire audio blocks associated with a plurality of audio channels.
32. An apparatus as defined in claim 20 wherein the unpacking unit is to obtain compression information associated with the first compressed digital data stream.
33. An apparatus as defined in claim 20 wherein the first compressed digital data stream is associated with a main audio service and the second digital data stream is associated with an auxiliary audio service.
34. An apparatus as defined in claim 20 further comprising a repacking unit to repack the frame based on a plurality of mixed transform coefficient sets.
35. A tangible machine readable storage medium comprising instructions which, when executed, cause a machine to:
acquire a frame associated with a first compressed digital bit stream;
unpack the frame to obtain a plurality of original transform coefficient sets; and
modify the plurality of original transform coefficient sets to mix a second digital bit stream with the first compressed digital bit stream, wherein the instructions, when executed, cause the machine to modify the plurality of original transform coefficient sets by:
36. A storage medium as defined in claim 35 wherein the instructions, when executed, cause the machine to determine the first mantissa code associated with the mixed transform coefficient of the one of the plurality of mixed transform coefficient sets by:
determining a quantization step size associated with the corresponding original transform coefficient of one of the plurality of original transformed coefficient sets;
37. A storage medium as defined in claim 35 wherein the instructions, when executed, cause the machine to modify the plurality of original transform coefficient sets by:
38. A storage medium as defined in claim 35 wherein the instructions, when executed, further cause the machine to generate the plurality of mixed coefficient sets by determining mantissa codes associated with mixed transform coefficients of each of the plurality of mixed coefficient sets based on compression information associated with the first compressed digital bit stream.
39. A storage medium as defined in claim 35 wherein the instructions, when executed, further cause the machine to acquire the frame associated with the first compressed digital bit stream by acquiring audio blocks associated with at least one of a plurality of audio channels.
40. A storage medium as defined in claim 35 wherein the instructions, when executed, cause the machine to unpack the frame to obtain the plurality of original transform coefficient sets by identifying compression information associated with the first compressed digital bit stream.
41. A storage medium as defined in claim 35 wherein the instructions, when executed, further cause the machine to repack the frame based on a plurality of mixed transform coefficient sets.
42. A storage medium as defined in claim 35 wherein the first compressed digital bit stream is associated with a main audio service and the second digital bit stream is associated with an auxiliary audio service.
43. A system to mix digital data streams comprising
a first source to provide a first compressed digital data stream;
a second source to provide a second digital data stream; and
a mixing device comprising a processor to mix the second digital data stream with the first compressed digital data stream without uncompressing the first compressed digital data stream, wherein the first compressed digital data stream comprises a plurality of original transform coefficients, and the mixing device is to modify the plurality of original transform coefficient sets to mix the second digital data stream with the first compressed digital data stream by:
substituting the first mantissa code associated with the mixed transform coefficient for a second mantissa code associated with a corresponding original transform coefficient of one of a plurality of transform coefficient sets.
44. A system as defined in claim 43 wherein the plurality of original transform coefficients comprises respective pluralities of original mantissas and original exponents, and the mixing device is to modify only the plurality of original mantissas to modify the plurality of original transform coefficients.
45. A system as defined in claim 44 wherein the mixing device is to modify the plurality of original transform coefficients by determining the plurality of mixed transform coefficients based on the second digital data stream and compression information associated with the first compressed digital data stream.
46. A system as defined in claim 45 wherein the compression information comprises at least one quantization step size.
47. A system as defined in claim 45 wherein determining the plurality of mixed transform coefficients comprises quantizing a plurality of mixed mantissas associated with the mixed transform coefficients.
48. A system as defined in claim 47 wherein the mixing device is to modify the plurality of original mantissas based on the plurality of quantized mixed mantissas and the compression information.
49. A system as defined in claim 43 wherein the first compressed digital data stream is compressed according to an audio compression standard.
50. A system as defined in claim 43 wherein the first compressed digital data stream is associated with a main audio service and the second digital data stream is associated with an auxiliary data service.
51. A system as defined in claim 43 wherein the second digital data stream is uncompressed.
52. A method as of combining a first compressed digital data stream with a second digital data stream, the method comprising:
acquiring a frame associated with the first compressed digital data stream;
modifying the plurality of original transform coefficient sets to combine the second digital data stream with the first compressed digital data stream, wherein modifying the plurality of original transform coefficient sets comprises:
53. A method as defined in claim 52 wherein combining comprises mixing and wherein modifying the plurality of original transform coefficient sets to combine the second digital data stream with the first compressed digital data stream comprises modifying the plurality of original transform coefficient sets to mix the second digital data stream with the first compressed digital data stream.
54. A method as defined in claim 52 wherein each of the plurality of original transform coefficient sets comprises one or more modified discrete cosine transform coefficients.
US11571483 2004-07-02 2005-06-29 Methods and apparatus for mixing compressed digital bit streams Active 2029-07-27 US8412363B2 (en)
US58511504 true 2004-07-02 2004-07-02
US58635404 true 2004-07-08 2004-07-08
PCT/US2005/023578 WO2006014362A1 (en) 2004-07-02 2005-06-29 Methods and apparatus for mixing compressed digital bit streams
US11571483 US8412363B2 (en) 2004-07-02 2005-06-29 Methods and apparatus for mixing compressed digital bit streams
PCT/US2005/023578 A-371-Of-International WO2006014362A1 (en) 2004-07-02 2005-06-29 Methods and apparatus for mixing compressed digital bit streams
US13800249 Continuation US9191581B2 (en) 2004-07-02 2013-03-13 Methods and apparatus for mixing compressed digital bit streams
US20080253440A1 true US20080253440A1 (en) 2008-10-16
US8412363B2 true US8412363B2 (en) 2013-04-02
ID=35787402
US11571483 Active 2029-07-27 US8412363B2 (en) 2004-07-02 2005-06-29 Methods and apparatus for mixing compressed digital bit streams
US13800249 Active 2026-02-02 US9191581B2 (en) 2004-07-02 2013-03-13 Methods and apparatus for mixing compressed digital bit streams
US (2) US8412363B2 (en)
EP (1) EP1779297A4 (en)
KR (1) KR101087588B1 (en)
CN (2) CN1993700B (en)
CA (1) CA2572622A1 (en)
WO (1) WO2006014362A1 (en)
KR101053161B1 (en) * 2009-07-22 2011-08-02 주식회사 엠씨넥스 H.264 / avc video synthesis method and apparatus in a compressed domain
AU2010200873B2
AU2004258470B2
AU2005270105B2
US20120039504A1 (en) 2003-06-13 2012-02-16 Venugopal Srinivasan Methods and apparatus for embedding watermarks
US20120022879A1 (en) 2006-10-11 2012-01-26 Venugopal Srinivasan Methods and apparatus for embedding codes in compressed audio data streams
Cheng et al., "Enhanced Spread Spectrum Watermarking of MPEG-2, AAC Audio, " Department of Electrical Engineering, Texas A&M University, College Station, T.X., U.S.A., and Panasonic Information and Networking Technologies Lab, Princeton, N.J., U.S.A., pp. IV-3728-IV-3731, 2002 (4 pages).
CIPO, "Notice of Acceptance," issued in connection with Canadian Patent Application No. 2,529,310, on Mar. 8, 2012 (1 page).
De Smet et al., Subband Based MPEG Audio Mixing for Internet Streaming Applications, ICASSP 2001, 4 pages.
EPO, "First Examination Report," issued in connection with European Patent Application No. 04776572.2, dated Apr. 25, 2012 (4 pages).
EPO, "First Examination Report," issued in connection with European Patent Application No. 05780308.2, dated Nov. 18, 2011 (9 pages).
EPO, "Summons to Attend Oral Proceedings Pursuant to Rule 115(1) EPC," issued in connection with European Patent Application No. 05780308.2, dated Jan. 2, 2013 (4 pages).
European Patent Office, Supplementary European Search Report for EP Application No. 05780308.2, Jun. 24, 2010, 5 pages.
Grant A. Davidson, "Digital Audio Coding: Dolby AC-3", pp. 41-1-41-21, 21 Pages.
International Preliminary Examining Authority, International Preliminary Report on Patentability for Application No. PCT/US2005/023578, Aug. 25, 2006, 20 pages.
International Searching Authority, International Search Report and Written Opinion of the International Searching Authority for Application No. PCT/US2005/023578, Jan. 11, 2006, 8 pages.
IP Australia, "Examiner's First Report," issued in connection with AU Application No. 2005270105, mailed on Feb. 22, 2010 (2 pages).
IP Australia, "First Examination Report," issued in connection with Australian Patent Application No. 2011203047, mailed on Feb. 8, 2012 (2 pages).
IP Australia, "Notice of Acceptance," issued in connection with Australian Patent Application No. 2005270105, mailed on Mar. 18, 2011 (4 pages).
IP Australia, "Notice of Acceptance," issued in connection with Australian Patent Application No. 2010200873, mailed on Aug. 22, 2012 (3 pages).
Patent Cooperation Treaty, "International Preliminary Report on Patentability," issued by the International Searching Authority in connection with PCT Application No. PCT/US2004/018953, mailed Jan. 4, 2006 (22 pages).
Patent Cooperation Treaty, "International Search Report and Written Opinion," issued by the International Searching Authority in connection with PCT Application No. PCT/US07/80973, mailed Apr. 23, 2008, (7 pages).
Patent Cooperation Treaty, "International Search Report," issued by the International Searching Authority in connection with PCT Application No. PCT/US2004/018645, mailed Apr. 19, 2005 (4 pages).
Patent Cooperation Treaty, "Written Opinion" issued by the International Searching Authority in connection with PCT Application No. PCT/US2004/018645, mailed Apr. 19, 2005 (5 pages).
PCT, "International Preliminary Report on Patentability," issued by the International Searching Authority in connection with PCT Application No. PCT/US2004/018645, issued Dec. 13, 2005 (6 pages).
PCT, "International Search Report and Written Opinion," issued by the International Searching Authority in connection with PCT Application No. PCT/US2004/018953, mailed Apr. 29, 2005 (8 pages).
SIPO, "Notice of Decision of Granting Patent Right for Invention," issued in connection with Chinese Patent Application No. 200580026107.2, issued on Oct. 20, 2011 (5 pages).
SIPO, "Notice of Decision of Granting Patent Right for Invention," issued in connection with Chinese Patent Application No. 201010501205.X, issued on Aug. 30, 2012 (3 pages).
SIPO, "Second Notification of Office Action," issued in connection with Chinese Patent Application No. 201010501205.X, issued on Feb. 20, 2012 (6 pages).
State Intellectual Property Office of China, "Second Notification of Office Action," issued in connection with Chinese Patent Application No. 200580026107.2, issued on Jun. 9, 2011, (6 pages).
Taiwan International Property Office, "Office Action," issued in connection with PCT Application No. 93117000, mailed Nov. 4, 2010 (6 pages).
Toumi et al., A Summation Algorithm for MPEG-1 Coded Audio Signals: A First Step Towards Audio Processing in the Compressed Domain, Annals of Telecommunications, vol. 55, No. 3-4, Mar. 1, 2000, 10 pages.
United States Patent and Trademark Office, "Office Action," issued in connection with U.S. Appl. No. 12/613,334, mailed on Nov. 15, 2010 (24 pages).
USPTO, "Notice of Allowance," issued in connection with U.S. Appl. No. 11/870,275, mailed on Sep. 26, 2011 (5 pages).
USPTO, "Notice of Allowance," issued in connection with U.S. Appl. No. 12/613,334, mailed on Oct. 13, 2011 (11 pages).
USPTO, "Notice of Allowance," issued in connection with U.S. Appl. No. 13/283,271, mailed on Sep. 18, 2012 (11 pages).
USPTO, "Office Action," issued in connection with U.S. Appl. No. 11/870,275, mailed on Nov. 23, 2010, (37 pages).
USPTO, "Office Action," issued in connection with U.S. Appl. No. 12/613,334, mailed on Apr. 26, 2011, (7 pages).
USPTO, "Office Action," issued in connection with U.S. Appl. No. 13/283,271, mailed on May 3, 2012 (6 pages).
USPTO, "Supplemental Notice of Allowance," issued in connection with U.S. Appl. No. 11/870,275, mailed on Oct. 5, 2011 (3 pages).
CA2572622A1 (en) 2006-02-09 application
KR20070039123A (en) 2007-04-11 application
WO2006014362A1 (en) 2006-02-09 application
US20130194507A1 (en) 2013-08-01 application
EP1779297A4 (en) 2010-07-28 application
KR101087588B1 (en) 2011-11-29 grant
CN1993700B (en) 2012-03-14 grant
US9191581B2 (en) 2015-11-17 grant
EP1779297A1 (en) 2007-05-02 application
US20080253440A1 (en) 2008-10-16 application
CN102592638A (en) 2012-07-18 application
CN1993700A (en) 2007-07-04 application
US8983834B2 (en) 2015-03-17 Multichannel audio coding
JP2005523480A (en) 2005-08-04 Parameter display of spatial audio
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:SRINIVASAN, VENUGOPAL;REEL/FRAME:017720/0769
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:PEIFFER, JOHN C.;REEL/FRAME:018331/0753
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:SRINIVASAN, VENUGOPAL;PEIFFER, JOHN C.;REEL/FRAME:018926/0159
Free format text: MERGER;ASSIGNOR:NIELSEN MEDIA RESEARCH, LLC (FORMERLY KNOWN AS NIELSEN MEDIA RESEARCH, INC.);REEL/FRAME:022995/0305