Gets the sample that is at the given index for the given tag in the given
list and copies it into the variable pointed to by @sample. Free the sample
with gst_sample_unref() when it is no longer needed. You can retrieve the
buffer from the sample using gst_sample_get_buffer() and the associated
caps (if any) with gst_sample_get_caps().
Gets the sample that is at the given index for the given tag in the given list and copies it into the variable pointed to by @sample. Free the sample with gst_sample_unref() when it is no longer needed. You can retrieve the buffer from the sample using gst_sample_get_buffer() and the associated caps (if any) with gst_sample_get_caps().
Free-function: gst_sample_unref