USBB13AP77016-XXX-B06 NEC Electronics, USBB13AP77016-XXX-B06 Datasheet - Page 20

• Manufacturer Part Number: USBB13AP77016-XXX-B06
• Description: DSP middleware(AMR voice CODEC)
• Manufacturer: NEC Electronics

2.2.3 amr_EncodeFrame function
the silence compression function is set to ON during initialization, the silence compression function is automatically
enabled in accordance with speech input.
20
The amr_EncodeFrame function compresses speech data of 16 bits × 160 samples at a specified bit rate. When
[Classification]
[Function name]
[Summary of function] Compresses speech of one frame (160 samples) at a specified bit rate.
[Format]
[Argument]
[Return value]
[Registers used]
[Hardware resources] Maximum stack level:
Remark When calling this function, be sure to first secure static memory and scratch memory areas. For
details, refer to 2.3 Memory Structure.
MR475
MR515
MR59
MR67
MR74
MR795
MR102
MR122
MRDTX
Codec Mode
Encode processing function
amr_EncodeFrame
call amr_EncodeFrame
R0, R1, R2, R3, R4, R5, R6, R7, DP0, DP1, DP2, DP3, DP4, DP5, DP6, DP7, DN0, DN1,
DN2, DN3, DN4, DN5, DN6, DN7, DMX, DMY
Maximum loop stack level:
Maximum number of repetitions:
Maximum number of MIPS:
Register
Register
Register
Register
Type
Type
Table 2-2. Operation Mode of Encoder/Decoder
Value
CHAPTER 2 LIBRARY SPECIFICATIONS
0
1
2
3
4
5
6
7
8
Return Value
Argument
Compression/decompression mode at 4.75 Kbps
Compression/decompression mode at 5.15 Kbps
Compression/decompression mode at 5.90 Kbps
Compression/decompression mode at 6.70 Kbps
Compression/decompression mode at 7.40 Kbps
Compression/decompression mode at 7.95 Kbps
Compression/decompression mode at 10.20 Kbps
Compression/decompression mode at 12.20 Kbps
Compression/decompression mode when silence compression
function is enabled
User’s Manual U15165EJ3V0UM
DP4
DP0
R0L
R0L
Encode mode (see Table 2-2, excluding MRDTX)
First address of speech input buffer
First address of bit stream output buffer
Encode mode used for compression (see Table 2-2)
21.7
5
3
239
Description
Description
Description