xref: /aosp_15_r20/external/tensorflow/tensorflow/lite/experimental/microfrontend/lib/log_scale.h (revision b6fb3261f9314811a0f4371741dbb8839866f948)
1 /* Copyright 2018 The TensorFlow Authors. All Rights Reserved.
2 
3 Licensed under the Apache License, Version 2.0 (the "License");
4 you may not use this file except in compliance with the License.
5 You may obtain a copy of the License at
6 
7     http://www.apache.org/licenses/LICENSE-2.0
8 
9 Unless required by applicable law or agreed to in writing, software
10 distributed under the License is distributed on an "AS IS" BASIS,
11 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 See the License for the specific language governing permissions and
13 limitations under the License.
14 ==============================================================================*/
15 #ifndef TENSORFLOW_LITE_EXPERIMENTAL_MICROFRONTEND_LIB_LOG_SCALE_H_
16 #define TENSORFLOW_LITE_EXPERIMENTAL_MICROFRONTEND_LIB_LOG_SCALE_H_
17 
18 #include <stdint.h>
19 #include <stdlib.h>
20 
21 #ifdef __cplusplus
22 extern "C" {
23 #endif
24 
25 struct LogScaleState {
26   int enable_log;
27   int scale_shift;
28 };
29 
30 // Applies a fixed point logarithm to the signal and converts it to 16 bit. Note
31 // that the signal array will be modified.
32 uint16_t* LogScaleApply(struct LogScaleState* state, uint32_t* signal,
33                         int signal_size, int correction_bits);
34 
35 #ifdef __cplusplus
36 }  // extern "C"
37 #endif
38 
39 #endif  // TENSORFLOW_LITE_EXPERIMENTAL_MICROFRONTEND_LIB_LOG_SCALE_H_
40