diff options
| -rw-r--r-- | libs/audiographer/audiographer/general/silence_trimmer.h | 178 |
1 files changed, 90 insertions, 88 deletions
diff --git a/libs/audiographer/audiographer/general/silence_trimmer.h b/libs/audiographer/audiographer/general/silence_trimmer.h index 8959c8674a..e7ae089028 100644 --- a/libs/audiographer/audiographer/general/silence_trimmer.h +++ b/libs/audiographer/audiographer/general/silence_trimmer.h @@ -74,8 +74,8 @@ class /*LIBAUDIOGRAPHER_API*/ SilenceTrimmer TypeUtils<T>::zero_fill (silence_buffer, silence_buffer_size); } - in_beginning = true; - in_end = false; + processed_data = false; + processing_finished = false; trim_beginning = false; trim_end = false; silence_frames = 0; @@ -90,8 +90,8 @@ class /*LIBAUDIOGRAPHER_API*/ SilenceTrimmer */ void add_silence_to_beginning (framecnt_t frames_per_channel) { - if (throw_level (ThrowObject) && !in_beginning) { - throw Exception(*this, "Tried to add silence to beginning after already outputting data"); + if (throw_level (ThrowObject) && processed_data) { + throw Exception(*this, "Tried to add silence to beginning after processing started"); } add_to_beginning = frames_per_channel; } @@ -102,8 +102,8 @@ class /*LIBAUDIOGRAPHER_API*/ SilenceTrimmer */ void add_silence_to_end (framecnt_t frames_per_channel) { - if (throw_level (ThrowObject) && in_end) { - throw Exception(*this, "Tried to add silence to end after already reaching end"); + if (throw_level (ThrowObject) && processed_data) { + throw Exception(*this, "Tried to add silence to end after processing started"); } add_to_end = frames_per_channel; } @@ -114,8 +114,8 @@ class /*LIBAUDIOGRAPHER_API*/ SilenceTrimmer */ void set_trim_beginning (bool yn) { - if (throw_level (ThrowObject) && !in_beginning) { - throw Exception(*this, "Tried to set beginning trim after already outputting data"); + if (throw_level (ThrowObject) && processed_data) { + throw Exception(*this, "Tried to set beginning trim after processing started"); } trim_beginning = yn; } @@ -126,8 +126,8 @@ class /*LIBAUDIOGRAPHER_API*/ SilenceTrimmer */ void set_trim_end (bool yn) { - if (throw_level (ThrowObject) && in_end) { - throw Exception(*this, "Tried to set end trim after already reaching end"); + if (throw_level (ThrowObject) && processed_data) { + throw Exception(*this, "Tried to set end trim after processing started"); } trim_end = yn; } @@ -146,16 +146,14 @@ class /*LIBAUDIOGRAPHER_API*/ SilenceTrimmer check_flags (*this, c); - if (throw_level (ThrowStrict) && in_end) { + if (throw_level (ThrowStrict) && processing_finished) { throw Exception(*this, "process() after reaching end of input"); } - // delay end of input propagation until after all output is complete - in_end = c.has_flag (ProcessContext<T>::EndOfInput); + // delay end of input propagation until output/processing is complete + processing_finished = c.has_flag (ProcessContext<T>::EndOfInput); c.remove_flag (ProcessContext<T>::EndOfInput); - framecnt_t frame_index = 0; - /* TODO this needs a general overhaul. * * - decouple "required silence duration" from buffer-size. @@ -164,103 +162,83 @@ class /*LIBAUDIOGRAPHER_API*/ SilenceTrimmer * -> allocate a buffer "hold time" worth of samples. * check if all samples in buffer are above/below threshold, * - * * in_beginning, in_end may be in the same cycle. - * * end-trim should not be on a buffersize boundary - * * results should be consistent for all buffer-sizes and samplerates - * - * (currently this is mosly fine because the "Chunker" - * produces a fixAed 8K stream, but this 8K are for interleaved - * data all channels and it's regardless of sample-rate) - * * https://github.com/x42/silan/blob/master/src/main.c#L130 * may lend itself for some inspiration. */ - if (in_beginning) { - - bool has_data = true; - - // only check silence if doing either of these - // This will set both has_data and frame_index - if (add_to_beginning || trim_beginning) { - has_data = find_first_non_silent_frame (c, frame_index); - } - - // Added silence if there is silence to add - if (add_to_beginning) { - - if (debug_level (DebugVerbose)) { - debug_stream () << DebugUtils::demangled_name (*this) << - " adding to beginning" << std::endl; + framecnt_t output_start_index = 0; + framecnt_t output_sample_count = c.frames(); + + if (!processed_data) { + if (trim_beginning) { + framecnt_t first_non_silent_frame_index = 0; + if (find_first_non_silent_frame (c, first_non_silent_frame_index)) { + // output from start of non-silent data until end of buffer + // output_sample_count may also be altered in trim end + output_start_index = first_non_silent_frame_index; + output_sample_count = c.frames() - first_non_silent_frame_index; + processed_data = true; + } else { + // keep entering this block until non-silence is found to trim + processed_data = false; } + } else { + processed_data = true; + } - add_to_beginning *= c.channels(); + // This block won't be called again so add silence to beginning + if (processed_data && add_to_beginning) { + add_to_beginning *= c.channels (); output_silence_frames (c, add_to_beginning); } + } - // If we are not trimming the beginning, output everything - // Then has_data = true and frame_index = 0 - // Otherwise these reflect the silence state - if (has_data) { - - if (debug_level (DebugVerbose)) { - debug_stream () << DebugUtils::demangled_name (*this) << - " outputting whole frame to beginning" << std::endl; - } + if (processed_data) { + if (trim_end) { + framecnt_t first_non_silent_frame_index = 0; + if (find_first_non_silent_frame (c, first_non_silent_frame_index)) { + // context buffer contains non-silent data, flush any intermediate silence + output_silence_frames (c, silence_frames); - in_beginning = false; - ConstProcessContext<T> c_out (c, &c.data()[frame_index], c.frames() - frame_index); - ListedSource<T>::output (c_out); - } + framecnt_t silent_frame_index = 0; + find_last_silent_frame_reverse (c, silent_frame_index); - } else if (trim_end) { // Only check zero samples if trimming end + // Count of samples at end of block that are "silent", may be zero. + framecnt_t silent_end_samples = c.frames () - silent_frame_index; + framecnt_t samples_before_silence = c.frames() - silent_end_samples; - if (find_first_non_silent_frame (c, frame_index)) { + assert (samples_before_silence + silent_end_samples == c.frames ()); - if (debug_level (DebugVerbose)) { - debug_stream () << DebugUtils::demangled_name (*this) << - " flushing intermediate silence and outputting frame" << std::endl; - } + // output_start_index may be non-zero if start trim occurred above + output_sample_count = samples_before_silence - output_start_index; - // context contains non-zero data - output_silence_frames (c, silence_frames); // flush intermediate silence - ListedSource<T>::output (c); // output rest of data - } else { // whole context is zero + // keep track of any silent samples not output + silence_frames = silent_end_samples; - if (debug_level (DebugVerbose)) { - debug_stream () << DebugUtils::demangled_name (*this) << - " no, output, adding frames to silence count" << std::endl; + } else { + // whole context buffer is silent output nothing + silence_frames += c.frames (); + output_sample_count = 0; } - - silence_frames += c.frames(); - } - - } else { // no need to do anything special - - if (debug_level (DebugVerbose)) { - debug_stream () << DebugUtils::demangled_name (*this) << - " outputting whole frame in middle" << std::endl; } - ListedSource<T>::output (c); + // now output data if any + ConstProcessContext<T> c_out (c, &c.data()[output_start_index], output_sample_count); + ListedSource<T>::output (c_out); } - // Finally, if in end, add silence to end - if (in_end && add_to_end) { - if (debug_level (DebugVerbose)) { - debug_stream () << DebugUtils::demangled_name (*this) << - " adding to end" << std::endl; - } - + // Finally, if in last process call, add silence to end + if (processing_finished && processed_data && add_to_end) { add_to_end *= c.channels(); output_silence_frames (c, add_to_end); } - if (in_end) { + if (processing_finished) { // reset flag removed previous to processing above c.set_flag (ProcessContext<T>::EndOfInput); // Finally mark write complete by writing nothing with EndOfInput set + // whether or not any data has been written ConstProcessContext<T> c_out(c, silence_buffer, 0); c_out().set_flag (ProcessContext<T>::EndOfInput); ListedSource<T>::output (c_out); @@ -270,7 +248,7 @@ class /*LIBAUDIOGRAPHER_API*/ SilenceTrimmer using Sink<T>::process; - private: +private: bool find_first_non_silent_frame (ProcessContext<T> const & c, framecnt_t & result_frame) { @@ -285,6 +263,31 @@ class /*LIBAUDIOGRAPHER_API*/ SilenceTrimmer return false; } + /** + * Reverse find the last silent frame index. If the last sample in the + * buffer is non-silent the index will be one past the end of the buffer and + * equal to c.frames(). e.g silent_end_samples = c.frames() - result_frame + * + * @return true if result_frame index is valid, false if there were only + * silent samples in the context buffer + */ + bool find_last_silent_frame_reverse (ProcessContext<T> const & c, framecnt_t & result_frame) + { + framecnt_t last_sample_index = c.frames() - 1; + + for (framecnt_t i = last_sample_index; i != 0; --i) { + if (!tester.is_silent (c.data()[i])) { + result_frame = i; + // Round down to nearest interleaved "frame" beginning + result_frame -= result_frame % c.channels(); + // Round up to return the "last" silent interleaved frame + result_frame += c.channels(); + return true; + } + } + return false; + } + void output_silence_frames (ProcessContext<T> const & c, framecnt_t & total_frames) { assert (!c.has_flag (ProcessContext<T>::EndOfInput)); @@ -302,9 +305,8 @@ class /*LIBAUDIOGRAPHER_API*/ SilenceTrimmer } } - - bool in_beginning; - bool in_end; + bool processed_data; + bool processing_finished; bool trim_beginning; bool trim_end; |