python 动态调整控件大小_在python中的GStreamer管道中动态调整图像大小

I am trying to create a program to do various animations on different images simultaneously and one of the effects I am trying to achieve is zooming into a picture which is achieved by keeping base frame of a fixed size and image size to increase and decrease. But when I try to dynamically change the size of an image it causes error I tried searching in the web but couldn't find the right solution to it. Below is my code. Could anyone suggest me the right examples from which I can learn it will be grateful (Preferably python examples).

#!/usr/bin/python

import gobject

import time

gobject.threads_init()

import pygst

pygst.require("0.10")

import gst

p = gst.parse_launch("""uridecodebin uri=file:///home/jango/Pictures/3.jpg name=src1 ! queue ! videoscale ! ffmpegcolorspace !

imagefreeze ! capsfilter name=vfps caps="video/x-raw-yuv, framerate=60/1, width=200, height=150" ! mix.

uridecodebin uri=file:///home/jango/Pictures/2.jpg name=src2 ! queue ! videoscale ! ffmpegcolorspace !

imagefreeze ! video/x-raw-yuv, framerate=60/1, width=200, height=150 ! mix.

uridecodebin uri=file:///home/jango/Pictures/1.jpg name=src ! queue ! videoscale ! ffmpegcolorspace !

imagefreeze ! video/x-raw-yuv, framerate=60/1, width=200, height=150 ! mix.

uridecodebin uri=file:///home/jango/Pictures/mia_martine.jpg ! queue ! videoscale ! ffmpegcolorspace !

imagefreeze ! video/x-raw-yuv, framerate=60/1, width=200, height=150 ! mix.

uridecodebin uri=file:///home/jango/Pictures/4.jpg ! queue ! videoscale ! ffmpegcolorspace !

imagefreeze ! video/x-raw-yuv, framerate=60/1, width=200, height=150 ! mix.

uridecodebin uri=file:///home/jango/Pictures/mia_marina1.jpg ! queue ! videoscale ! ffmpegcolorspace !

imagefreeze ! video/x-raw-yuv, framerate=60/1, width=200, height=150 ! mix.

videotestsrc pattern=2 ! video/x-raw-yuv, framerate=10/1, width=1024, height=768 ! videomixer name=mix sink_6::zorder=0 ! ffmpegcolorspace ! theoraenc ! oggmux name=mux !

filesink location=1.ogg

filesrc location=/home/jango/Music/mp3/flute_latest.mp3 ! decodebin ! audioconvert ! vorbisenc ! queue ! mux.

""")

m = p.get_by_name("mix")

s0 = m.get_pad("sink_0")

s0.set_property("zorder", 1)

q = s0.get_caps()

q.make_writable()

control11 = gst.Controller.props

control = gst.Controller(s0, "ypos", "alpha", "xpos")

control.set_interpolation_mode("ypos", gst.INTERPOLATE_LINEAR)

control.set_interpolation_mode("alpha", gst.INTERPOLATE_LINEAR)

control.set_interpolation_mode("xpos", gst.INTERPOLATE_LINEAR)

control.set("ypos", 0, 0)

control.set("ypos", 5 * gst.SECOND, 600)

control.set("xpos", 0, 0)

control.set("xpos", 5 * gst.SECOND, 500)

control.set("alpha", 0, 0)

control.set("alpha", 5 * gst.SECOND, 1.0)

s1 = m.get_pad("sink_1")

s1.set_property("zorder", 2)

control1 = gst.Controller(s1, "xpos", "alpha")

control1.set_interpolation_mode("xpos", gst.INTERPOLATE_LINEAR)

control1.set_interpolation_mode("alpha", gst.INTERPOLATE_LINEAR)

control1.set("xpos", 0, 0)

control1.set("xpos", 5 * gst.SECOND, 500)

control1.set("alpha", 0, 0)

control1.set("alpha", 5 * gst.SECOND, 1.0)

#

s2 = m.get_pad("sink_2")

s2.set_property("zorder", 3)

control2 = gst.Controller(s2, "ypos", "alpha", "xpos")

control2.set_interpolation_mode("ypos", gst.INTERPOLATE_LINEAR)

control2.set_interpolation_mode("xpos", gst.INTERPOLATE_LINEAR)

control2.set_interpolation_mode("alpha", gst.INTERPOLATE_LINEAR)

control2.set("xpos", 0, 0)

control2.set("xpos", 5 * gst.SECOND, 500)

control2.set("ypos", 0, 0)

control2.set("ypos", 5 * gst.SECOND, 300)

control2.set("alpha", 0, 0)

control2.set("alpha", 5 * gst.SECOND, 1.0)

s3 = m.get_pad("sink_3")

s3.set_property("zorder", 4)

control3 = gst.Controller(s3, "ypos", "alpha", "xpos")

control3.set_interpolation_mode("ypos", gst.INTERPOLATE_LINEAR)

control3.set_interpolation_mode("alpha", gst.INTERPOLATE_LINEAR)

control3.set_interpolation_mode("xpos", gst.INTERPOLATE_LINEAR)

control3.set("ypos", 0, 0)

control3.set("ypos", 5 * gst.SECOND, 600)

control3.set("xpos", 0, 0)

control3.set("xpos", 5 * gst.SECOND, 200)

control3.set("alpha", 0, 0)

control3.set("alpha", 5 * gst.SECOND, 1.0)

s4 = m.get_pad("sink_4")

s4.set_property("zorder", 5)

control4 = gst.Controller(s4, "ypos", "alpha", "xpos")

control4.set_interpolation_mode("ypos", gst.INTERPOLATE_LINEAR)

control4.set_interpolation_mode("alpha", gst.INTERPOLATE_LINEAR)

control4.set_interpolation_mode("xpos", gst.INTERPOLATE_LINEAR)

control4.set("ypos", 0, 0)

control4.set("ypos", 5 * gst.SECOND, 300)

control4.set("xpos", 0, 0)

control4.set("xpos", 5 * gst.SECOND, 200)

control4.set("alpha", 0, 0)

control4.set("alpha", 5 * gst.SECOND, 1.0)

s5 = m.get_pad("sink_5")

s5.set_property("zorder", 6)

control5 = gst.Controller(s5, "ypos", "alpha", "xpos")

control5.set_interpolation_mode("ypos", gst.INTERPOLATE_LINEAR)

control5.set_interpolation_mode("alpha", gst.INTERPOLATE_LINEAR)

control5.set_interpolation_mode("xpos", gst.INTERPOLATE_LINEAR)

control5.set("ypos", 0, 0)

control5.set("ypos", 5 * gst.SECOND, 0)

control5.set("xpos", 0, 0)

control5.set("xpos", 5 * gst.SECOND, 200)

control5.set("alpha", 0, 0)

control5.set("alpha", 5 * gst.SECOND, 1.0)

p.set_state(gst.STATE_PLAYING)

time.sleep(3)

p.set_state(gst.STATE_READY)

m = p.get_by_name("mix")

s0 = m.get_pad("sink_0")

q = s0.get_caps()

print q

if q.is_fixed():

print "not doable"

else:

caps = gst.caps_from_string("video/x-raw-yuv, framerate=60/1, width=1000, height=1000")

s0.set_caps(caps)

p.set_state(gst.STATE_PLAYING)

gobject.MainLoop().run()

It will be great if anyone could show me a good learning spot for GStreamer tutorials for python developers.

解决方案

You can change image size dynamically, but for that you must have some condition

Firstly your pipeline should be build something like that source ! videorate ! ffvideoscale ! colorspace ! capsfilter caps="caps" ....

Secondly in python you get caps property from capsfilters element and you change the resolution in caps.

This should be working, warning if I remember you must add a gobject.timeout_add than 100 ms between resolution change.