Content for TS 46.060 Word version: 18.0.0
3 Definitions, symbols and abbreviations
4 Outline description
5 Functional description of the encoder
6 Functional description of the decoder
7 Variables, constants and tables in the C-code of the GSM EFR codec
8 Homing sequences
9 Bibliography
$ Change History
3 Definitions, symbols and abbreviations p. 6
4 Outline description p. 11
4.1 Functional description of audio parts p. 11
4.2 Preparation of speech samples p. 12
4.3 Principles of the GSM enhanced full rate speech encoder p. 12
4.4 Principles of the GSM enhanced full rate speech decoder p. 14
4.5 Sequence and subjective importance of encoded parameters p. 14
5 Functional description of the encoder p. 14
5.1 Pre-processing p. 14
5.2 Linear prediction analysis and quantization p. 15
5.2.1 Windowing and auto-correlation computation p. 15
5.2.2 Levinson-Durbin algorithm p. 16
5.2.3 LP to LSP conversion p. 17
5.2.4 LSP to LP conversion p. 18
5.2.5 Quantization of the LSP coefficients p. 19
5.2.6 Interpolation of the LSPs p. 20
5.3 Open-loop pitch analysis p. 20
5.4 Impulse response computation p. 21
5.5 Target signal computation p. 21
5.6 Adaptive codebook search p. 22
5.7 Algebraic codebook structure and search p. 23
5.8 Quantization of the fixed codebook gain p. 26
5.9 Memory update p. 27
6 Functional description of the decoder p. 27
6.1 Decoding and speech synthesis p. 27
6.2 Post-processing p. 29
6.2.1 Adaptive post-filtering p. 29
6.2.2 Up-scaling p. 30
7 Variables, constants and tables in the C-code of the GSM EFR codec p. 30
8 Homing sequences p. 33
8.1 Functional description p. 33
8.2 Definitions p. 33
8.3 Encoder homing p. 35
8.4 Decoder homing p. 35
8.5 Encoder home state p. 36
8.6 Decoder home state p. 37
9 Bibliography p. 42
$ Change History p. 43
