OBO | 基于Android JNI HTTPS libevent mysql/redis

I am using oboe library to make a music app. There I produce music by writing PCM float values to the given pointer. I rarely have underruns which I can hearwhich. I also verify this with the following oboe APIs:

I have a moleculer-based microservice that has an endpoint which outputs a large JSON object (around tens of thousands of objects)

This is a structured JSON object and I know beforehand what it is going to look like.

I understand that in R it is best to avoid loops where possible. In that regard, I would like to perform the function of the code below but without using the nested loops.

The loops check whether the f'th element of the vector things_I_want_to_find is present in the i'th row of thing_to_be_searched. For example, when both i and f are 1, the code checks whether "vocals" is present in john's row. Because "vocals" is present in john's row, the name and instrument are added to vectors instrument and name. When both loops are complete these two vectors can be combined in a data.frame.

I know that there is the apply() family of functions in R but I don't know if they are able to be used in this case. Has anyone got any helpful hints or suggestions?

I have three applications participating the AzureAD OBO flow :

1. Angular FrontEnd --> Registered with AzureAD as OIDC app

2. ASP.NET Core Web API --> Registered with AzureAD as SAML app

3. NAV OData Service --> Registered with AzureAD as SAML app

Here goes the complete flow :

1. Angular frontend application signs a user into Azure AD and request a delegated access token for Web API 1 (ASP.NET Core Web API)

2. Client application then calls Web API 1 with the issued access token

3. Web API 1 in turn needs to call a downstream Web API 2 (NAV OData Services) so it uses its access token (in step 2 above) to request an access token for Web API 2. What happens in this step is that Web API 1 uses the OBO flow to exchange its access token for another resource’s access token. The exchanged token is still issued on behalf of the original sign in user and it has delegated permission.

4. Web API 1 uses the new access token to call Web API 2

In the above I am getting error in the Step 3.

Error details :

I'm trying to implement Oboe library into my application, so I can perform low latency audio playing. I could perform panning, playback manipulation, sound scaling, etc. I've been asking few questions about this topic because I'm completely new to audio worlds.

Now I can perform basic things which internal Android audio class such as SoundPool provides. I can play multiple sounds simultaneously without noticeable delays.

But now I encountered another problem. So I made very simple application for example; There is button in screen and if user taps this screen, it plays simple piano sound. However fast user taps this button, it must be able to mix those same piano sounds just like what SoundPool does.

My codes can do this very well, until I taps button too much times, so there are many audio queues to be mixed.

I created an Azure KeyVault that I want my App Service to be able to access. From what I can tell, the principal of my App Service should have access to the KeyVault, but I always get the following error when trying to retrieve from it. This happens whether I am running locally in Visual Studio or in Azure.

Service request failed. Status: 403 (Forbidden) Content: {"error":{"code":"Forbidden","message":"The policy requires the caller 'appid=MY_APP_ID;oid=MY_PRINCIPAL_ID_STARTING_WITH_1A5 ;iss=https://sts.windows.net/REDACTED_GUID/' to use on-behalf-of (OBO) flow. For more information on OBO, please see https://go.microsoft.com/fwlink/?linkid=2152310","innererror":{"code":"ForbiddenByPolicy"}}} Headers: Pragma: no-cache x-ms-keyvault-region: westus x-ms-client-request-id: REDACTED x-ms-request-id: REDACTED x-ms-keyvault-service-version: 1.2.236.0 x-ms-keyvault-network-info: conn_type=Ipv4;addr=52.155.40.204;act_addr_fam=InterNetwork; Strict-Transport-Security: REDACTED X-Content-Type-Options: REDACTED Content-Length: 387 Cache-Control: no-cache Content-Type: application/json; charset=utf-8 Date: Wed, 21 Apr 2021 20:10:33 GMT Expires: -1 X-Powered-By: REDACTED

I have looked at the linked KB article and it talks about OAUTH`. I am not trying to use OAUTH, so I don't understand why that is relevant.

Here is the access policy in my KeyVault:

Here is the screenshot from the App Service where I configured a principal.

It clearly says at the bottom that it can be configured to access other resources, so I don't understand why it cannot access KeyVault.

Code used to attempt to access.

I'm trying to implement Oboe library to my project to perform the least latency when playing sounds. I could perform playback manipulating, panning, mixing, the basics things which internal Android library such as SoundPool can provide.

I wanted to test panning effect, I connected headphones to my device, but then, I noticed that any sound didn't play through my headphones. Device speaker also didn't play any sound either. So I disconnected my headphones to check if something went wrong. I pressed sound playing button, but I couldn't hear any sound even though headphones are completely disconnected from device.

When I firstly open the app, it can play sound through device speaker without any problems, but as soon as I connect headphones, no sound plays through both device speaker and headphones.

Same for opposite, if I start app with headphones connected to device, it can play sound very well through headphones. It can even perform panning effect too, but if I disconnect headphones from device, it stops playing any sound.

1. Do I have to re-open audio stream whenever preferred audio device is changed?
2. If yes for 1, is there any way to notify app that audio device is changed, so I can manually close stream and re-open it? Or can I make Oboe automatically handle audio device changes?

I'm developing Flutter plugin which is targeting only Android for now. It's kind of synthesis thing; Users can load audio file into memory, and they can adjust pitch (not pitch shift) and play multiple sound with the least delay using audio library called Oboe.

I managed to get PCM data from audio files which MediaCodec class supports, and also succeeded to handle pitch by manipulating playback via accessing PCM array manually too.

This PCM array is stored as float array, ranging from -1.0 to 1.0. I now want to support panning feature, just like what internal Android class such as SoundPool. I'm planning to follow how SoundPool is handling panning. There are 2 values I have to pass to SoundPool when performing panning effect : left, and right. These 2 values are float, and must range from 0.0 to 1.0.

For example, if I pass (1.0F, 0.0F), then users can hear sound only by left ear. (1.0F, 1.0F) will be normal (center). Panning wasn't problem... until I encountered handling stereo sounds. I know what to do to perform panning with stereo PCM data, but I don't know how to perform natural panning.

If I try to shift all sound to left side, then right channel of sound must be played in left side. In opposite, if I try to shift all sound to right side, then left channel of sound must be played in right side. I also noticed that there is thing called Panning Rule, which means that sound must be a little bit louder when it's shifted to side (about +3dB). I tried to find a way to perform natural panning effect, but I really couldn't find algorithm or reference of it.

Below is structure of float stereo PCM array, I actually didn't modify array when decoding audio files, so it should be common structure

Say I have a pandas DataFrame as below: