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GStreamer Core Plugins 0.10 Plugins Reference Manual | ![]() |
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"current-level-buffers" guint : Read "current-level-bytes" guint : Read "current-level-time" guint64 : Read "leaky" GstQueueLeaky : Read / Write "max-size-buffers" guint : Read / Write "max-size-bytes" guint : Read / Write "max-size-time" guint64 : Read / Write "min-threshold-buffers" guint : Read / Write "min-threshold-bytes" guint : Read / Write "min-threshold-time" guint64 : Read / Write
Data is queued until one of the limits specified by the "max-size-buffers", "max-size-bytes" and/or "max-size-time" properties has been reached. Any attempt to push more buffers into the queue will block the pushing thread until more space becomes available.
The queue will create a new thread on the source pad to decouple the processing on sink and source pad.
You can query how many buffers are queued by reading the "current-level-buffers" property. You can track changes by connecting to the notify::current-level-buffers signal (which like all signals will be emitted from the streaming thread). The same applies to the "current-level-time" and "current-level-bytes" properties.
The default queue size limits are 200 buffers, 10MB of data, or one second worth of data, whichever is reached first.
As said earlier, the queue blocks by default when one of the specified maximums (bytes, time, buffers) has been reached. You can set the "leaky" property to specify that instead of blocking it should leak (drop) new or old buffers.
The "underrun" signal is emitted when the queue has less data than the specified minimum thresholds require (by default: when the queue is empty). The "overrun" signal is emitted when the queue is filled up. Both signals are emitted from the context of the streaming thread.
"current-level-buffers"
property"current-level-buffers" guint : Read
Current number of buffers in the queue.
Default value: 0
"current-level-bytes"
property"current-level-bytes" guint : Read
Current amount of data in the queue (bytes).
Default value: 0
"current-level-time"
property"current-level-time" guint64 : Read
Current amount of data in the queue (in ns).
Default value: 0
"leaky"
property"leaky" GstQueueLeaky : Read / Write
Where the queue leaks, if at all.
Default value: Not Leaky
"max-size-buffers"
property"max-size-buffers" guint : Read / Write
Max. number of buffers in the queue (0=disable).
Default value: 200
"max-size-bytes"
property"max-size-bytes" guint : Read / Write
Max. amount of data in the queue (bytes, 0=disable).
Default value: 10485760
"max-size-time"
property"max-size-time" guint64 : Read / Write
Max. amount of data in the queue (in ns, 0=disable).
Default value: 1000000000
"min-threshold-buffers"
property"min-threshold-buffers" guint : Read / Write
Min. number of buffers in the queue to allow reading (0=disable).
Default value: 0
"min-threshold-bytes"
property"min-threshold-bytes" guint : Read / Write
Min. amount of data in the queue to allow reading (bytes, 0=disable).
Default value: 0
"overrun"
signalvoid user_function (GstQueue *queue, gpointer user_data) : Run First
Reports that the buffer became full (overrun). A buffer is full if the total amount of data inside it (num-buffers, time, size) is higher than the boundary values which can be set through the GObject properties.
queue : |
the queue instance |
user_data : |
user data set when the signal handler was connected. |
"running"
signalvoid user_function (GstQueue *queue, gpointer user_data) : Run First
Reports that enough (min-threshold) data is in the queue. Use this signal together with the underrun signal to pause the pipeline on underrun and wait for the queue to fill-up before resume playback.
queue : |
the queue instance |
user_data : |
user data set when the signal handler was connected. |
"underrun"
signalvoid user_function (GstQueue *queue, gpointer user_data) : Run First
Reports that the buffer became empty (underrun). A buffer is empty if the total amount of data inside it (num-buffers, time, size) is lower than the boundary values which can be set through the GObject properties.
queue : |
the queue instance |
user_data : |
user data set when the signal handler was connected. |
"pushing"
signalvoid user_function (GstQueue *queue, gpointer user_data) : Run First
Reports when the queue has enough data to start pushing data again on the source pad.
queue : |
the queue instance |
user_data : |
user data set when the signal handler was connected. |