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* iBasso DX50/DX90: Major code cleanup and reorganization.Udo Schläpfer2015-02-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Reorganization - Separated iBasso devices from PLATFORM_ANDROID. These are now standlone hosted targets. Most device specific code is in the firmware/target/hosted/ibasso directory. - No dependency on Android SDK, only the Android NDK is needed. 32 bit Android NDK and Android API Level 16. - Separate implementation for each device where feasible. Code cleanup - Rewrite of existing code, from simple reformat to complete reimplementation. - New backlight interface, seperating backlight from touchscreen. - Rewrite of device button handler, removing unneeded code and fixing memory leaks. - New Debug messages interface logging to Android adb logcat (DEBUGF, panicf, logf). - Rewrite of lcd device handler, removing unneeded code and fixing memory leaks. - Rewrite of audiohw device handler/pcm interface, removing unneeded code and fixing memory leaks, enabling 44.1/48kHz pthreaded playback. - Rewrite of power and powermng, proper shutdown, using batterylog results (see http://gerrit.rockbox.org/r/#/c/1047/). - Rewrite of configure (Android NDK) and device specific config. - Rewrite of the Android NDK specific Makefile. Misc - All plugins/games/demos activated. - Update tinyalsa to latest from https://github.com/tinyalsa/tinyalsa. Includes - http://gerrit.rockbox.org/r/#/c/993/ - http://gerrit.rockbox.org/r/#/c/1010/ - http://gerrit.rockbox.org/r/#/c/1035/ Does not include http://gerrit.rockbox.org/r/#/c/1007/ due to new backlight interface and new option for hold switch, touchscreen, physical button interaction. Rockbox needs the iBasso DX50/DX90 loader for startup, see http://gerrit.rockbox.org/r/#/c/1099/ The loader expects Rockbox to be installed in /mnt/sdcard/.rockbox/. If /mnt/sdcard/ is accessed as USB mass storage device, Rockbox will exit gracefully and the loader will restart Rockbox on USB disconnect. Tested on iBasso DX50. Compiled (not tested) for iBasso DX90. Compiled (not tested) for PLATFORM_ANDROID. Change-Id: I5f5e22e68f5b4cf29c28e2b40b2c265f2beb7ab7
* DSP Compressor: Sidechain, Exponential Atk/RlsRyan Billing2013-12-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is an improvement to the current compressor which I have added to my own Sansa Fuze V2 build. I am submitting here in case others find it interesting. Features added to the existing compressor: Attack, Look-ahead, Sidechain Filtering. Exponential attack and release characteristic response. Benefits from adding missing features: Attack: Preserve perceived "brightness" of tone by letting onset transients come through at a higher level than the rest of the compressed program material. Look-ahead: With Attack comes clipping on the leading several cycles of a transient onset. With look-ahead function, this can be pre-emptively mitigated with a slower gain change (less distortion). Look-ahead limiting is implemented to prevent clipping while keeping gain change ramp to an interval near 3ms instead of instant attack. The existing compressor implementation distorts the leading edge of a transient by causing instant gain change, resulting in log() distortion. This sounds "woofy" to me. Exponential Attack/Release: eMore natural sounding. On attack, this is a true straight line of 10dB per attack interval. Release is a little different, however, sounds natural as an analog compressor. Sidechain Filtering: Mild high-pass filter reduces response to low frequency onsets. For example, a hard kick drum is less likely to make the whole of the program material appear to fade in and out. Combined with a moderate attack time, such a transient will ride through with minimal audible artifact. Overall these changes make dynamic music sound more "open", more natural. The goal of a compressor is to make dyanamic music sound louder without necessarily sounding as though it has been compressed. I believe these changes come closer to this goal. Enjoy. If not, I am enjoying it Change-Id: I664eace546c364b815b4dc9ed4a72849231a0eb2 Reviewed-on: http://gerrit.rockbox.org/626 Tested: Purling Nayuki <cyq.yzfl@gmail.com> Reviewed-by: Michael Giacomelli <giac2000@hotmail.com>
* Enable setting of global output samplerate on certain targets.Michael Sevakis2013-07-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Replaces the NATIVE_FREQUENCY constant with a configurable frequency. The user may select 48000Hz if the hardware supports it. The default is still 44100Hz and the minimum is 44100Hz. The setting is located in the playback settings, under "Frequency". "Frequency" was duplicated in english.lang for now to avoid having to fix every .lang file for the moment and throwing everything out of sync because of the new play_frequency feature in features.txt. The next cleanup should combine it with the one included for recording and generalize the ID label. If the hardware doesn't support 48000Hz, no setting will be available. On particular hardware where very high rates are practical and desireable, the upper bound can be extended by patching. The PCM mixer can be configured to play at the full hardware frequency range. The DSP core can configure to the hardware minimum up to the maximum playback setting (some buffers must be reserved according to the maximum rate). If only 44100Hz is supported or possible on a given target for playback, using the DSP and mixer at other samperates is possible if the hardware offers them. Change-Id: I6023cf0c0baa8bc6292b6919b4dd3618a6a25622 Reviewed-on: http://gerrit.rockbox.org/479 Reviewed-by: Michael Sevakis <jethead71@rockbox.org> Tested-by: Michael Sevakis <jethead71@rockbox.org>
* Missed removing a couple unwanted includes in previous commit.Michael Sevakis2013-05-27
| | | | | | Get those too. Change-Id: Id2a39afe7a61d6ec0cea38633b94fe1b7122204f
* Remove explicit config.h and system.h includes from DSP code.Michael Sevakis2013-05-27
| | | | | | | Replace with rbcodecconfig.h and platform.h includes. Remove now- unneeded ones as well. Change-Id: I6111b71e90bf86d9fe272a7916f2d34a5c6dd724
* Cleanup and simplify latest DSP code incarnation.Michael Sevakis2013-05-04
| | | | | | | | | | | | | | Some things can just be a bit simpler in handling the list of stages and some things, especially format change handling, can be simplified for each stage implementation. Format changes are sent through the configure() callback. Hide some internal details and variables from processing stages and let the core deal with it. Do some miscellaneous cleanup and keep things a bit better factored. Change-Id: I19dd8ce1d0b792ba914d426013088a49a52ecb7e
* Make rbcodec/dsp includes more specific.Michael Sevakis2012-04-29
| | | | Change-Id: Idb6af40df26f5b8499a40e8b98602261ef227044
* Make compressor_update static.Michael Sevakis2012-04-29
| | | | Change-Id: Ic29242b4c397e82c2bee3808492a2d0a9ffebbe6
* Fundamentally rewrite much of the audio DSP.Michael Sevakis2012-04-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Creates a standard buffer passing, local data passing and messaging system for processing stages. Stages can be moved to their own source files to reduce clutter and ease assimilation of new ones. dsp.c becomes dsp_core.c which supports an engine and framework for effects. Formats and change notifications are passed along with the buffer so that they arrive at the correct time at each stage in the chain regardless of the internal delays of a particular one. Removes restrictions on the number of samples that can be processed at a time and it pays attention to destination buffer size restrictions without having to limit input count, which also allows pcmbuf to remain fuller and safely set its own buffer limits as it sees fit. There is no longer a need to query input/output counts given a certain number of input samples; just give it the sizes of the source and destination buffers. Works in harmony with stages that are not deterministic in terms of sample input/output ratio (like both resamplers but most notably the timestretch). As a result it fixes quirks with timestretch hanging up with certain settings and it now operates properly throughout its full settings range. Change-Id: Ib206ec78f6f6c79259c5af9009fe021d68be9734 Reviewed-on: http://gerrit.rockbox.org/200 Reviewed-by: Michael Sevakis <jethead71@rockbox.org> Tested-by: Michael Sevakis <jethead71@rockbox.org>
* Consolidate compressor settings into a struct.Michael Sevakis2012-04-26
| | | | | | Doing that makes things cleaner for later on. Change-Id: I4e279aa57ace16a348acc0fc09059592325ec95f
* Build librbcodec with DSP and metadata.Sean Bartell2012-03-18
All associated files are moved to /lib/rbcodec. Change-Id: I572ddd2b8a996aae1e98c081d06b1ed356dce222