| /* |
| * Copyright (C) 2014 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #ifndef ANDROID_AUDIO_CHANNELS_H |
| #define ANDROID_AUDIO_CHANNELS_H |
| |
| #include <system/audio.h> |
| |
| #ifdef __cplusplus |
| |
| // New development in channels namespace. |
| namespace android::audio_utils::channels { |
| |
| /** |
| * Returns a particular side (left, right, center) associated |
| * with a channel position mask bit index. |
| * This is a fixed geometrical constant for a given channel mask. |
| * |
| * For the channel mask spec, see system/media/audio/include/system/audio*.h. |
| * |
| * Special Note: if there are two LFE speakers and bass management is used, |
| * then AUDIO_CHANNEL_OUT_LOW_FREQUENCY speaker is on the left side and receives |
| * all bass from left side speakers that they cannot reproduce, |
| * likewise AUDIO_CHANNEL_OUT_LOW_FREQUENCY_2 is used for the right side |
| * (https://www.itu.int/dms_pub/itu-r/opb/rep/R-REP-BS.2159-4-2012-PDF-E.pdf#page=15). |
| * |
| * For simplicity, both AUDIO_CHANNEL_OUT_LOW_FREQUENCY and |
| * AUDIO_CHANNEL_OUT_LOW_FREQUENCY_2 are assigned to the center channel, |
| * which is a safe approximation given the lack of directionality of LFE. |
| * Specific handling for the presence of two LFE speakers must be handled |
| * elsewhere. |
| * |
| * \param idx index of bit in the channel position mask. |
| * \return side constant. |
| */ |
| enum AUDIO_GEOMETRY_SIDE { |
| AUDIO_GEOMETRY_SIDE_LEFT, |
| AUDIO_GEOMETRY_SIDE_CENTER, |
| AUDIO_GEOMETRY_SIDE_RIGHT, |
| }; |
| // static constexpr arrays cannot be declared in block scope. |
| // inline allows multiple definition, single object address. |
| constexpr inline AUDIO_GEOMETRY_SIDE kSideFromChannelIdx[] = { |
| AUDIO_GEOMETRY_SIDE_LEFT, // AUDIO_CHANNEL_OUT_FRONT_LEFT = 0x1u, |
| AUDIO_GEOMETRY_SIDE_RIGHT, // AUDIO_CHANNEL_OUT_FRONT_RIGHT = 0x2u, |
| AUDIO_GEOMETRY_SIDE_CENTER, // AUDIO_CHANNEL_OUT_FRONT_CENTER = 0x4u, |
| AUDIO_GEOMETRY_SIDE_CENTER, // AUDIO_CHANNEL_OUT_LOW_FREQUENCY = 0x8u, |
| AUDIO_GEOMETRY_SIDE_LEFT, // AUDIO_CHANNEL_OUT_BACK_LEFT = 0x10u, |
| AUDIO_GEOMETRY_SIDE_RIGHT, // AUDIO_CHANNEL_OUT_BACK_RIGHT = 0x20u, |
| AUDIO_GEOMETRY_SIDE_LEFT, // AUDIO_CHANNEL_OUT_FRONT_LEFT_OF_CENTER = 0x40u, |
| AUDIO_GEOMETRY_SIDE_RIGHT, // AUDIO_CHANNEL_OUT_FRONT_RIGHT_OF_CENTER = 0x80u, |
| AUDIO_GEOMETRY_SIDE_CENTER, // AUDIO_CHANNEL_OUT_BACK_CENTER = 0x100u, |
| AUDIO_GEOMETRY_SIDE_LEFT, // AUDIO_CHANNEL_OUT_SIDE_LEFT = 0x200u, |
| AUDIO_GEOMETRY_SIDE_RIGHT, // AUDIO_CHANNEL_OUT_SIDE_RIGHT = 0x400u, |
| AUDIO_GEOMETRY_SIDE_CENTER, // AUDIO_CHANNEL_OUT_TOP_CENTER = 0x800u, |
| AUDIO_GEOMETRY_SIDE_LEFT, // AUDIO_CHANNEL_OUT_TOP_FRONT_LEFT = 0x1000u, |
| AUDIO_GEOMETRY_SIDE_CENTER, // AUDIO_CHANNEL_OUT_TOP_FRONT_CENTER = 0x2000u, |
| AUDIO_GEOMETRY_SIDE_RIGHT, // AUDIO_CHANNEL_OUT_TOP_FRONT_RIGHT = 0x4000u, |
| AUDIO_GEOMETRY_SIDE_LEFT, // AUDIO_CHANNEL_OUT_TOP_BACK_LEFT = 0x8000u, |
| AUDIO_GEOMETRY_SIDE_CENTER, // AUDIO_CHANNEL_OUT_TOP_BACK_CENTER = 0x10000u, |
| AUDIO_GEOMETRY_SIDE_RIGHT, // AUDIO_CHANNEL_OUT_TOP_BACK_RIGHT = 0x20000u, |
| AUDIO_GEOMETRY_SIDE_LEFT, // AUDIO_CHANNEL_OUT_TOP_SIDE_LEFT = 0x40000u, |
| AUDIO_GEOMETRY_SIDE_RIGHT, // AUDIO_CHANNEL_OUT_TOP_SIDE_RIGHT = 0x80000u, |
| AUDIO_GEOMETRY_SIDE_LEFT, // AUDIO_CHANNEL_OUT_BOTTOM_FRONT_LEFT = 0x100000u, |
| AUDIO_GEOMETRY_SIDE_CENTER, // AUDIO_CHANNEL_OUT_BOTTOM_FRONT_CENTER = 0x200000u, |
| AUDIO_GEOMETRY_SIDE_RIGHT, // AUDIO_CHANNEL_OUT_BOTTOM_FRONT_RIGHT = 0x400000u, |
| AUDIO_GEOMETRY_SIDE_CENTER, // AUDIO_CHANNEL_OUT_LOW_FREQUENCY_2 = 0x800000u, |
| AUDIO_GEOMETRY_SIDE_LEFT, // AUDIO_CHANNEL_OUT_FRONT_WIDE_LEFT = 0x1000000u |
| AUDIO_GEOMETRY_SIDE_RIGHT, // AUDIO_CHANNEL_OUT_FRONT_WIDE_RIGHT = 0x2000000u |
| }; |
| constexpr inline AUDIO_GEOMETRY_SIDE sideFromChannelIdx(size_t idx) { |
| static_assert(std::size(kSideFromChannelIdx) == FCC_26); |
| if (idx < std::size(kSideFromChannelIdx)) return kSideFromChannelIdx[idx]; |
| return AUDIO_GEOMETRY_SIDE_CENTER; |
| } |
| |
| /** |
| * Returns a particular height (bottom, middle, top) associated |
| * with a channel position mask bit index. |
| * This is a fixed geometrical constant for a given channel mask. |
| * |
| * For the channel mask spec, see system/media/audio/include/system/audio*.h. |
| * |
| * \param idx index of bit in the channel position mask. |
| * \return height constant. |
| */ |
| enum AUDIO_GEOMETRY_HEIGHT { |
| AUDIO_GEOMETRY_HEIGHT_BOTTOM, |
| AUDIO_GEOMETRY_HEIGHT_MIDDLE, |
| AUDIO_GEOMETRY_HEIGHT_TOP, |
| }; |
| // static constexpr arrays cannot be declared in block scope. |
| // inline allows multiple definition, single object address. |
| constexpr inline AUDIO_GEOMETRY_HEIGHT kHeightFromChannelIdx [] = { |
| AUDIO_GEOMETRY_HEIGHT_MIDDLE, // AUDIO_CHANNEL_OUT_FRONT_LEFT = 0x1u, |
| AUDIO_GEOMETRY_HEIGHT_MIDDLE, // AUDIO_CHANNEL_OUT_FRONT_RIGHT = 0x2u, |
| AUDIO_GEOMETRY_HEIGHT_MIDDLE, // AUDIO_CHANNEL_OUT_FRONT_CENTER = 0x4u, |
| AUDIO_GEOMETRY_HEIGHT_BOTTOM, // AUDIO_CHANNEL_OUT_LOW_FREQUENCY = 0x8u, |
| AUDIO_GEOMETRY_HEIGHT_MIDDLE, // AUDIO_CHANNEL_OUT_BACK_LEFT = 0x10u, |
| AUDIO_GEOMETRY_HEIGHT_MIDDLE, // AUDIO_CHANNEL_OUT_BACK_RIGHT = 0x20u, |
| AUDIO_GEOMETRY_HEIGHT_MIDDLE, // AUDIO_CHANNEL_OUT_FRONT_LEFT_OF_CENTER = 0x40u, |
| AUDIO_GEOMETRY_HEIGHT_MIDDLE, // AUDIO_CHANNEL_OUT_FRONT_RIGHT_OF_CENTER = 0x80u, |
| AUDIO_GEOMETRY_HEIGHT_MIDDLE, // AUDIO_CHANNEL_OUT_BACK_CENTER = 0x100u, |
| AUDIO_GEOMETRY_HEIGHT_MIDDLE, // AUDIO_CHANNEL_OUT_SIDE_LEFT = 0x200u, |
| AUDIO_GEOMETRY_HEIGHT_MIDDLE, // AUDIO_CHANNEL_OUT_SIDE_RIGHT = 0x400u, |
| AUDIO_GEOMETRY_HEIGHT_TOP, // AUDIO_CHANNEL_OUT_TOP_CENTER = 0x800u, |
| AUDIO_GEOMETRY_HEIGHT_TOP, // AUDIO_CHANNEL_OUT_TOP_FRONT_LEFT = 0x1000u, |
| AUDIO_GEOMETRY_HEIGHT_TOP, // AUDIO_CHANNEL_OUT_TOP_FRONT_CENTER = 0x2000u, |
| AUDIO_GEOMETRY_HEIGHT_TOP, // AUDIO_CHANNEL_OUT_TOP_FRONT_RIGHT = 0x4000u, |
| AUDIO_GEOMETRY_HEIGHT_TOP, // AUDIO_CHANNEL_OUT_TOP_BACK_LEFT = 0x8000u, |
| AUDIO_GEOMETRY_HEIGHT_TOP, // AUDIO_CHANNEL_OUT_TOP_BACK_CENTER = 0x10000u, |
| AUDIO_GEOMETRY_HEIGHT_TOP, // AUDIO_CHANNEL_OUT_TOP_BACK_RIGHT = 0x20000u, |
| AUDIO_GEOMETRY_HEIGHT_TOP, // AUDIO_CHANNEL_OUT_TOP_SIDE_LEFT = 0x40000u, |
| AUDIO_GEOMETRY_HEIGHT_TOP, // AUDIO_CHANNEL_OUT_TOP_SIDE_RIGHT = 0x80000u, |
| AUDIO_GEOMETRY_HEIGHT_BOTTOM, // AUDIO_CHANNEL_OUT_BOTTOM_FRONT_LEFT = 0x100000u, |
| AUDIO_GEOMETRY_HEIGHT_BOTTOM, // AUDIO_CHANNEL_OUT_BOTTOM_FRONT_CENTER = 0x200000u, |
| AUDIO_GEOMETRY_HEIGHT_BOTTOM, // AUDIO_CHANNEL_OUT_BOTTOM_FRONT_RIGHT = 0x400000u, |
| AUDIO_GEOMETRY_HEIGHT_BOTTOM, // AUDIO_CHANNEL_OUT_LOW_FREQUENCY_2 = 0x800000u, |
| AUDIO_GEOMETRY_HEIGHT_MIDDLE, // AUDIO_CHANNEL_OUT_FRONT_WIDE_LEFT = 0x1000000u |
| AUDIO_GEOMETRY_HEIGHT_MIDDLE, // AUDIO_CHANNEL_OUT_FRONT_WIDE_RIGHT = 0x2000000u |
| }; |
| constexpr inline AUDIO_GEOMETRY_HEIGHT heightFromChannelIdx(size_t idx) { |
| static_assert(std::size(kHeightFromChannelIdx) == FCC_26); |
| if (idx < std::size(kHeightFromChannelIdx)) return kHeightFromChannelIdx[idx]; |
| return AUDIO_GEOMETRY_HEIGHT_MIDDLE; |
| } |
| |
| /** |
| * Returns a particular depth (front, middle (aka side), back) associated |
| * with a channel position mask bit index. |
| * This is a fixed geometrical constant for a given channel mask. |
| * |
| * For the channel mask spec, see system/media/audio/include/system/audio*.h. |
| * |
| * \param idx index of bit in the channel position mask. |
| * \return depth constant. |
| */ |
| enum AUDIO_GEOMETRY_DEPTH { |
| AUDIO_GEOMETRY_DEPTH_FRONT, |
| AUDIO_GEOMETRY_DEPTH_MIDDLE, |
| AUDIO_GEOMETRY_DEPTH_BACK, |
| }; |
| // static constexpr arrays cannot be declared in block scope. |
| // inline allows multiple definition, single object address. |
| constexpr inline AUDIO_GEOMETRY_DEPTH kDepthFromChannelIdx[] = { |
| AUDIO_GEOMETRY_DEPTH_FRONT, // AUDIO_CHANNEL_OUT_FRONT_LEFT = 0x1u, |
| AUDIO_GEOMETRY_DEPTH_FRONT, // AUDIO_CHANNEL_OUT_FRONT_RIGHT = 0x2u, |
| AUDIO_GEOMETRY_DEPTH_FRONT, // AUDIO_CHANNEL_OUT_FRONT_CENTER = 0x4u, |
| AUDIO_GEOMETRY_DEPTH_FRONT, // AUDIO_CHANNEL_OUT_LOW_FREQUENCY = 0x8u, |
| AUDIO_GEOMETRY_DEPTH_BACK, // AUDIO_CHANNEL_OUT_BACK_LEFT = 0x10u, |
| AUDIO_GEOMETRY_DEPTH_BACK, // AUDIO_CHANNEL_OUT_BACK_RIGHT = 0x20u, |
| AUDIO_GEOMETRY_DEPTH_FRONT, // AUDIO_CHANNEL_OUT_FRONT_LEFT_OF_CENTER = 0x40u, |
| AUDIO_GEOMETRY_DEPTH_FRONT, // AUDIO_CHANNEL_OUT_FRONT_RIGHT_OF_CENTER = 0x80u, |
| AUDIO_GEOMETRY_DEPTH_BACK, // AUDIO_CHANNEL_OUT_BACK_CENTER = 0x100u, |
| AUDIO_GEOMETRY_DEPTH_MIDDLE, // AUDIO_CHANNEL_OUT_SIDE_LEFT = 0x200u, |
| AUDIO_GEOMETRY_DEPTH_MIDDLE, // AUDIO_CHANNEL_OUT_SIDE_RIGHT = 0x400u, |
| AUDIO_GEOMETRY_DEPTH_MIDDLE, // AUDIO_CHANNEL_OUT_TOP_CENTER = 0x800u, |
| AUDIO_GEOMETRY_DEPTH_FRONT, // AUDIO_CHANNEL_OUT_TOP_FRONT_LEFT = 0x1000u, |
| AUDIO_GEOMETRY_DEPTH_FRONT, // AUDIO_CHANNEL_OUT_TOP_FRONT_CENTER = 0x2000u, |
| AUDIO_GEOMETRY_DEPTH_FRONT, // AUDIO_CHANNEL_OUT_TOP_FRONT_RIGHT = 0x4000u, |
| AUDIO_GEOMETRY_DEPTH_BACK, // AUDIO_CHANNEL_OUT_TOP_BACK_LEFT = 0x8000u, |
| AUDIO_GEOMETRY_DEPTH_BACK, // AUDIO_CHANNEL_OUT_TOP_BACK_CENTER = 0x10000u, |
| AUDIO_GEOMETRY_DEPTH_BACK, // AUDIO_CHANNEL_OUT_TOP_BACK_RIGHT = 0x20000u, |
| AUDIO_GEOMETRY_DEPTH_MIDDLE, // AUDIO_CHANNEL_OUT_TOP_SIDE_LEFT = 0x40000u, |
| AUDIO_GEOMETRY_DEPTH_MIDDLE, // AUDIO_CHANNEL_OUT_TOP_SIDE_RIGHT = 0x80000u, |
| AUDIO_GEOMETRY_DEPTH_FRONT, // AUDIO_CHANNEL_OUT_BOTTOM_FRONT_LEFT = 0x100000u, |
| AUDIO_GEOMETRY_DEPTH_FRONT, // AUDIO_CHANNEL_OUT_BOTTOM_FRONT_CENTER = 0x200000u, |
| AUDIO_GEOMETRY_DEPTH_FRONT, // AUDIO_CHANNEL_OUT_BOTTOM_FRONT_RIGHT = 0x400000u, |
| AUDIO_GEOMETRY_DEPTH_FRONT, // AUDIO_CHANNEL_OUT_LOW_FREQUENCY_2 = 0x800000u, |
| AUDIO_GEOMETRY_DEPTH_MIDDLE, // AUDIO_CHANNEL_OUT_FRONT_WIDE_LEFT = 0x1000000u |
| AUDIO_GEOMETRY_DEPTH_MIDDLE, // AUDIO_CHANNEL_OUT_FRONT_WIDE_RIGHT = 0x2000000u |
| }; |
| constexpr inline AUDIO_GEOMETRY_DEPTH depthFromChannelIdx(size_t idx) { |
| static_assert(std::size(kDepthFromChannelIdx) == FCC_26); |
| if (idx < std::size(kDepthFromChannelIdx)) return kDepthFromChannelIdx[idx]; |
| return AUDIO_GEOMETRY_DEPTH_FRONT; |
| } |
| |
| /** |
| * Returns the pair channel position mask bit index as determined by |
| * AUDIO_GEOMETRY_SIDE_LEFT and AUDIO_GEOMETRY_SIDE_RIGHT characteristics. |
| * |
| * For example a bit index of 0 (AUDIO_CHANNEL_OUT_FRONT_LEFT) returns |
| * a pair bit index of 1 (AUDIO_CHANNEL_OUT_FRONT_RIGHT). |
| * |
| * If there is no left/right characteristic, then -1 is returned. |
| * For example, a bit index of 2 (AUDIO_CHANNEL_OUT_FRONT_CENTER) returns |
| * a pair bit index of -1 (doesn't exist). |
| * |
| * For the channel mask spec, see system/media/audio/include/system/audio*.h. |
| * |
| * \param idx index of bit in the channel position mask. |
| * \return index of bit of the pair if non-negative, or -1 if it doesn't exist. |
| */ |
| |
| #pragma push_macro("CHANNEL_ASSOCIATE") |
| #undef CHANNEL_ASSOCIATE |
| #define CHANNEL_ASSOCIATE(x, y) \ |
| [__builtin_ctz(x)] = __builtin_ctz(y), [__builtin_ctz(y)] = __builtin_ctz(x), |
| |
| #pragma GCC diagnostic push |
| #pragma GCC diagnostic ignored "-Winitializer-overrides" // we use override array assignment |
| |
| constexpr inline int kPairIdxFromChannelIdx[FCC_26] = { |
| [ 0 ... 25 ] = -1, // everything defaults to -1 unless overridden below. |
| CHANNEL_ASSOCIATE(AUDIO_CHANNEL_OUT_FRONT_LEFT, AUDIO_CHANNEL_OUT_FRONT_RIGHT) |
| // AUDIO_CHANNEL_OUT_FRONT_CENTER = 0x4u, |
| // AUDIO_CHANNEL_OUT_LOW_FREQUENCY = 0x8u, |
| CHANNEL_ASSOCIATE(AUDIO_CHANNEL_OUT_BACK_LEFT, AUDIO_CHANNEL_OUT_BACK_RIGHT) |
| CHANNEL_ASSOCIATE( |
| AUDIO_CHANNEL_OUT_FRONT_LEFT_OF_CENTER, AUDIO_CHANNEL_OUT_FRONT_RIGHT_OF_CENTER) |
| // AUDIO_CHANNEL_OUT_BACK_CENTER = 0x100u, |
| CHANNEL_ASSOCIATE(AUDIO_CHANNEL_OUT_SIDE_LEFT, AUDIO_CHANNEL_OUT_SIDE_RIGHT) |
| // AUDIO_CHANNEL_OUT_TOP_CENTER = 0x800u, |
| CHANNEL_ASSOCIATE(AUDIO_CHANNEL_OUT_TOP_FRONT_LEFT, AUDIO_CHANNEL_OUT_TOP_FRONT_RIGHT) |
| // AUDIO_CHANNEL_OUT_TOP_FRONT_CENTER = 0x2000u, |
| CHANNEL_ASSOCIATE(AUDIO_CHANNEL_OUT_TOP_BACK_LEFT, AUDIO_CHANNEL_OUT_TOP_BACK_RIGHT) |
| // AUDIO_CHANNEL_OUT_TOP_BACK_CENTER = 0x10000u, |
| CHANNEL_ASSOCIATE(AUDIO_CHANNEL_OUT_TOP_SIDE_LEFT, AUDIO_CHANNEL_OUT_TOP_SIDE_RIGHT) |
| CHANNEL_ASSOCIATE(AUDIO_CHANNEL_OUT_BOTTOM_FRONT_LEFT, AUDIO_CHANNEL_OUT_BOTTOM_FRONT_RIGHT) |
| // AUDIO_CHANNEL_OUT_BOTTOM_FRONT_CENTER = 0x200000u, |
| // AUDIO_CHANNEL_OUT_LOW_FREQUENCY_2 = 0x800000u, |
| CHANNEL_ASSOCIATE(AUDIO_CHANNEL_OUT_FRONT_WIDE_LEFT, AUDIO_CHANNEL_OUT_FRONT_WIDE_RIGHT) |
| }; |
| #pragma GCC diagnostic pop |
| #pragma pop_macro("CHANNEL_ASSOCIATE") |
| |
| constexpr inline ssize_t pairIdxFromChannelIdx(size_t idx) { |
| static_assert(std::size(kPairIdxFromChannelIdx) == FCC_26); |
| if (idx < std::size(kPairIdxFromChannelIdx)) return kPairIdxFromChannelIdx[idx]; |
| return -1; |
| } |
| |
| } // android::audio_utils::channels |
| |
| #endif // __cplusplus |
| |
| /** \cond */ |
| __BEGIN_DECLS |
| /** \endcond */ |
| |
| /** |
| * Expands or contracts sample data from one interleaved channel format to another. |
| * Expanded channels are filled with zeros and put at the end of each audio frame. |
| * Contracted channels are omitted from the end of each audio frame. |
| * |
| * \param in_buff points to the buffer of samples |
| * \param in_buff_chans Specifies the number of channels in the input buffer. |
| * \param out_buff points to the buffer to receive converted samples. |
| * \param out_buff_chans Specifies the number of channels in the output buffer. |
| * \param sample_size_in_bytes Specifies the number of bytes per sample. 1, 2, 3, 4 are |
| * currently valid. |
| * \param num_in_bytes size of input buffer in bytes |
| * |
| * \return |
| * the number of bytes of output data or 0 if an error occurs. |
| * |
| * \note |
| * The out and sums buffers must either be completely separate (non-overlapping), or |
| * they must both start at the same address. Partially overlapping buffers are not supported. |
| */ |
| size_t adjust_channels(const void* in_buff, size_t in_buff_chans, |
| void* out_buff, size_t out_buff_chans, |
| unsigned sample_size_in_bytes, size_t num_in_bytes); |
| |
| /** |
| * Expands or contracts sample data from one interleaved channel format to another. |
| * Extra expanded channels are left alone in the output buffer. |
| * Contracted channels are omitted from the end of each audio frame. |
| * |
| * \param in_buff points to the buffer of samples |
| * \param in_buff_chans Specifies the number of channels in the input buffer. |
| * \param out_buff points to the buffer to receive converted samples. |
| * \param out_buff_chans Specifies the number of channels in the output buffer. |
| * \param sample_size_in_bytes Specifies the number of bytes per sample. 1, 2, 3, 4 are |
| * currently valid. |
| * \param num_in_bytes size of input buffer in bytes |
| * |
| * \return |
| * the number of bytes of output data or 0 if an error occurs. |
| * |
| * \note |
| * The out and in buffers must either be completely separate (non-overlapping), or |
| * they must both start at the same address. Partially overlapping buffers are not supported. |
| */ |
| size_t adjust_selected_channels(const void* in_buff, size_t in_buff_chans, |
| void* out_buff, size_t out_buff_chans, |
| unsigned sample_size_in_bytes, size_t num_in_bytes); |
| |
| /** |
| * Expands or contracts sample data from one interleaved channel format to another. |
| * Extra expanded channels are interleaved in from the end of the input buffer. |
| * Contracted channels are copied to the end of the output buffer. |
| * |
| * \param in_buff points to the buffer of samples. |
| * \param in_buff_chans Specifies the number of channels in the input buffer. |
| * \param out_buff points to the buffer to receive converted samples. |
| * \param out_buff_chans Specifies the number of channels in the output buffer. |
| * \param sample_size_in_bytes Specifies the number of bytes per sample. 1, 2, 3, 4 are |
| * currently valid. |
| * \param num_in_bytes size of input buffer in bytes. |
| * |
| * \return |
| * the number of bytes of output data or 0 if an error occurs. |
| * |
| * \note |
| * The out and in buffers must be the same length. |
| * The out and in buffers must either be completely separate (non-overlapping), or |
| * they must both start at the same address. Partially overlapping buffers are not supported. |
| */ |
| size_t adjust_channels_non_destructive(const void* in_buff, size_t in_buff_chans, |
| void* out_buff, size_t out_buff_chans, |
| unsigned sample_size_in_bytes, size_t num_in_bytes); |
| |
| /** \cond */ |
| __END_DECLS |
| /** \endcond */ |
| |
| #endif // !ANDROID_AUDIO_CHANNELS_H |
