c - Gstreamer: capturing still frames from webcam with appsink? -


i have working c program streams continuous frames webcam appsink. however, i'm interested in capturing single frames when user presses key.

in other words: when idle, appsink receives no frames, when key pressed, appsink should pull single new frame camera source.

i've tried using output_selector "valve" switch frames between fakesink , appsink. when app idle, pipeline running, , looks like

v4l2src -> output_selector -> fakesink

and when want capture frame, change output_selector's active pad pipeline looks this:

v4l2src -> output_selector -> jpegenc -> appsink

then gst_app_sink_pull_sample() , switch active pad fakesink. issue (usually every other capture) duplicate frame that's same last one. how can resolve issue? there way achieve desired behavior?


Comments

Post a Comment

Popular posts from this blog

get url and add instance to a model with prefilled foreign key :django admin -

Image
i have page in each contest shown in row. each row contains contest id , link other model names have foreign key contest. news model: class news(models.model): title = models.charfield(max_length=50, null=true) description = models.textfield() time = models.timefield( default= datetime.datetime.now().time()) contest = models.foreignkey(contest) i want use admin adding , changing these models. want when user clicks on 'news' has foreign key contest id=1, shows list of news value foreign key. use {% instance in instances %} <tr class="{% cycle 'row1' 'row2' %}"> <td>{{ instance.title }}</td> <td>{{ instance.starttime }}</td> <td>{{ instance.timespan }}</td> <td>{{ instance.date }}</td> <td><a href="/adm...
Read more

android - Keyboard hides my half of edit-text and button below it even in scroll view -

i having trouble keyboard covers edit-text , half of button in scroll view. here's layout , please tell me how should resolve problem. many questions on topic none of them s working me. <?xml version="1.0" encoding="utf-8"?> <linearlayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:background="@drawable/bg" android:layout_height="match_parent"> <scrollview android:layout_width="match_parent" android:fillviewport="true" android:layout_height="match_parent"> <relativelayout android:layout_width="match_parent" android:layout_height="wrap_content" android:orientation="vertical"> <linearlayout android:layout_width="match_parent" android:layout_height="w...
Read more

css - Make div keyboard-scrollable in jQuery Mobile? -

from can tell, although jquery-mobile-powered pages can contain divs overflow set scroll or auto, , these divs can scrolled one-screen bar or mouse wheel, cannot scrolled using arrow keys, page-up/page-down, or home/end. instead, official "page" div (with data-role="page") absorbs input. perhaps other divs can't acquire focus, i'm not sure. is there way around this? edit: jsfiddle of simple example: https://jsfiddle.net/qogz0shx/ <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.4/jquery.min.js"></script> <script src="https://ajax.googleapis.com/ajax/libs/jquerymobile/1.4.5/jquery.mobile.min.js"> </script> <link rel="stylesheet" href="https://code.jquery.com/mobile/1.4.5/jquery.mobile-1.4.5.css"/> <style> #outer { overflow:scroll; height: 50vh; width: 50vw; } #inner { height: 500vh; width: 500vw; } ...
Read more