| CPC G10L 19/22 (2013.01) [G10L 19/032 (2013.01)] | 29 Claims |
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1. An audio encoder for encoding audio input data, comprising:
a preprocessor for preprocessing the audio input data to acquire audio data to be coded;
a coder processor for coding the audio data to be coded; and
a controller for controlling the coder processor so that, depending on a first signal characteristic of a first frame of the audio data to be coded, a number of audio data items of the audio data to be coded by the coder processor for the first frame is reduced compared to a second signal characteristic of a second frame, and a first number of information units used for coding the reduced number of audio data items for the first frame is enhanced compared to a second number of information units for the second frame,
wherein the coder processor comprises: a variable quantizer for quantizing the audio data of the first frame to acquire quantized audio data for the first frame and for quantizing the audio data of the second frame to acquire quantized audio data for the second frame; an initial coding stage for coding the quantized audio data of the first frame or the second frame; and a refinement coding stage for encoding residual data of the first frame and the second frame, wherein the controller is configured for analyzing the audio data of the first frame to determine a first control value for the variable quantizer for the first frame, for analyzing the audio data of the second frame to determine a second control value for the variable quantizer for the second frame, the second control value being different from the first control value, and for performing a manipulation of the audio data of the first frame or the second frame or of amplitude-related values derived from the audio data of the first frame or the second frame depending on the audio data for determining the first control value or the second control value, and wherein the variable quantizer is configured to quantize the audio data of the first frame or the second frame without the manipulation, or
wherein the first signal characteristic is a first tonality value, wherein the second signal characteristic is a second tonality value, and wherein the first tonality value indicates a higher tonality than the second tonality value, and wherein the controller is configured to reduce the number of audio data items for the first frame to a first number being smaller than the number of audio data items for the second frame, and to increase an average number of information units used for coding each audio data item of the reduced number of audio data items of the first frame to be greater than an average number of information units used for coding each audio data item of the reduced number of audio data items of the second frame, or
wherein the coder processor comprises the variable quantizer for quantizing the audio data of the first frame to acquire quantized audio data for the first frame and for quantizing the audio data of the second frame to acquire quantized audio data for the second frame; the initial coding stage for coding the quantized audio data of the first frame or the second frame; the refinement coding stage for encoding residual data of the first frame and the second frame; wherein the controller is configured for analyzing the audio data of the first frame to determine the first control value for the variable quantizer, for the initial coding stage or for an audio data item reducer for the first frame and for analyzing the audio data of the second frame to determine the second control value for the variable quantizer, for the initial coding stage or for an audio data item reducer for the second frame, the second control value being different from the first control value, and for determining a first tonality characteristic as the first signal characteristic to determine the first control value, and a second tonality characteristic as the second signal characteristic to determine the second control value so that a bit-budget for the refinement coding stage is increased in case of the first tonality characteristic compared to the bit-budget for the refinement coding stage in case of the second tonality characteristic, wherein the first tonality characteristic indicates a greater tonality then the second tonality characteristic, or
wherein the coder processor comprises the initial coding stage and the refinement coding stage, wherein the controller is configured to reduce the number of audio data items encoded by the initial coding stage for the first frame, wherein the initial coding stage is configured to code the reduced number of audio data items for the first frame using a first frame initial number of information units, and wherein the refinement coding stage is configured to use a first frame remaining number of information units for a refinement coding for the reduced number of audio data items for the first frame, wherein the first frame initial number of information units added to the first frame remaining number of information units results in a predetermined number of information units for the first frame, wherein the controller is configured to reduce the number of audio data items encoded by the initial coding stage for the second frame to a higher number of audio data items compared to the first frame, wherein the initial coding stage is configured to code the reduced number of audio data items for the second frame using a second frame initial number of information units, the second frame initial number of information units being higher than the first frame initial number of information units, and wherein the refinement coding stage is configured to use a second frame remaining number of information units for a refinement coding for the reduced number of audio data items for the second frame, wherein the second frame initial number of information units added to the second frame remaining number of information units results in the predetermined number of information units for the first frame.
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