在python中动态调整GStreamer管道中的图像大小

Question

我正在尝试创建一个程序来同时在不同的图像上制作各种动画，我要实现的效果之一是缩放到一个图片中，这是通过保持一个固定大小的底框和图像大小的增减来实现的。但是当我试图动态改变图像的大小时，它会导致错误，我尝试在web上搜索，但找不到正确的解决方案。下面是我的代码。如果有人能给我推荐正确的例子，我将不胜感激（最好是python示例）。在

#!/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()

如果有人能给我展示一个学习GStreamer python开发人员教程的好地方，那就太好了。在

Answer 1

您可以动态更改图像大小，但为此您必须具备某些条件

首先，你的管道应该建立像这样的来源！视频率！ffvideoscale！色彩空间！capsfilter caps=“caps”。。。。在

其次，在python中，从capsfilters元素获得caps属性，然后在caps中更改分辨率。在

这应该是有效的，警告如果我记得你必须添加一个gobject.timeout_添加分辨率变化之间超过100毫秒。在