【GStreamer 】3-1 gstreamer插件之 videotestsrc 介绍

编辑

1、简介

2、videotestsrc

3、videotestsrc 不同pattern参数测试罗列

3.1 (0): smpte - SMPTE 100% color bars

3.2 (1): snow - Random (television snow)

3.3 (2): black - 100% Black

编辑

3.4 checkers 方块

编辑

3.5 几何图形

4、videotestsrc 提供任意测试视频流

1、简介

书接上回，在第3章中我们做了雪球测试，其命令是：

#需要显示器支持
gst-launch-1.0 videotestsrc pattern=ball ! videoconvert ! autovideosink
#不需要硬件显示器支持 推荐
gst-launch-1.0 videotestsrc pattern=ball ! xvimagesink

其中有好几个插件我们其实都不是很清楚细节，这一部分，我们就补充说明，如何学习这些插件。也可以参考这个英文文档

videotestsrc

2、videotestsrc

videotestsrc 插件是一个视频源的插件，只有src pad，所以他只能生产数据，具体生产什么数据，需要一些参数指定，这个数据源可以帮助我们再没有硬件输出的时候，快速的实现一些测试。

#gst-inspect 工具查看插件信息 跟Element名。会列出Element的详细信息。例如，下面的命令会列出videotestsrc所支持的输入数据类型，Pad信息，支持的属性及值。我们主要关注Pad Template，以及Element的属性信息。
gst-inspect-1.0  videotestsrc

查询的输出内容

nvidia@nvidia-desktop:~$ gst-inspect-1.0  videotestsrc
Factory Details:Rank                     none (0)Long-name                Video test sourceKlass                    Source/VideoDescription              Creates a test video streamAuthor                   David A. Schleef <ds@schleef.org>

Plugin Details:Name                     videotestsrcDescription              Creates a test video streamFilename                 /usr/lib/aarch64-linux-gnu/gstreamer-1.0/libgstvideotestsrc.soVersion                  1.14.5License                  LGPLSource module            gst-plugins-baseSource release date      2019-05-29Binary package           GStreamer Base Plugins (Ubuntu)Origin URL               https://launchpad.net/distros/ubuntu/+source/gst-plugins-base1.0

GObject+----GInitiallyUnowned+----GstObject+----GstElement+----GstBaseSrc+----GstPushSrc+----GstVideoTestSrc

Pad Templates:SRC template: 'src'Availability: AlwaysCapabilities:video/x-rawformat: { (string)I420, (string)YV12, (string)YUY2, (string)UYVY, (string)AYUV, (string)RGBx, (string)BGRx, (string)xRGB, (string)xBGR, (string)RGBA, (string)BGRA, (string)ARGB, (string)ABGR, (string)RGB, (string)BGR, (string)Y41B, (string)Y42B, (string)YVYU, (string)Y444, (string)v210, (string)v216, (string)NV12, (string)NV21, (string)GRAY8, (string)GRAY16_BE, (string)GRAY16_LE, (string)v308, (string)RGB16, (string)BGR16, (string)RGB15, (string)BGR15, (string)UYVP, (string)A420, (string)RGB8P, (string)YUV9, (string)YVU9, (string)IYU1, (string)ARGB64, (string)AYUV64, (string)r210, (string)I420_10BE, (string)I420_10LE, (string)I422_10BE, (string)I422_10LE, (string)Y444_10BE, (string)Y444_10LE, (string)GBR, (string)GBR_10BE, (string)GBR_10LE, (string)NV16, (string)NV24, (string)NV12_64Z32, (string)A420_10BE, (string)A420_10LE, (string)A422_10BE, (string)A422_10LE, (string)A444_10BE, (string)A444_10LE, (string)NV61, (string)P010_10BE, (string)P010_10LE, (string)IYU2, (string)VYUY, (string)GBRA, (string)GBRA_10BE, (string)GBRA_10LE, (string)GBR_12BE, (string)GBR_12LE, (string)GBRA_12BE, (string)GBRA_12LE, (string)I420_12BE, (string)I420_12LE, (string)I422_12BE, (string)I422_12LE, (string)Y444_12BE, (string)Y444_12LE, (string)GRAY10_LE32, (string)NV12_10LE32, (string)NV16_10LE32 }width: [ 1, 2147483647 ]height: [ 1, 2147483647 ]framerate: [ 0/1, 2147483647/1 ]multiview-mode: { (string)mono, (string)left, (string)right }video/x-bayerformat: { (string)bggr, (string)rggb, (string)grbg, (string)gbrg }width: [ 1, 2147483647 ]height: [ 1, 2147483647 ]framerate: [ 0/1, 2147483647/1 ]multiview-mode: { (string)mono, (string)left, (string)right }

Element has no clocking capabilities.
Element has no URI handling capabilities.

Pads:SRC: 'src'Pad Template: 'src'

Element Properties:name                : The name of the objectflags: readable, writableString. Default: "videotestsrc0"parent              : The parent of the objectflags: readable, writableObject of type "GstObject"blocksize           : Size in bytes to read per buffer (-1 = default)flags: readable, writableUnsigned Integer. Range: 0 - 4294967295 Default: 4096 num-buffers         : Number of buffers to output before sending EOS (-1 = unlimited)flags: readable, writableInteger. Range: -1 - 2147483647 Default: -1 typefind            : Run typefind before negotiating (deprecated, non-functional)flags: readable, writable, deprecatedBoolean. Default: falsedo-timestamp        : Apply current stream time to buffersflags: readable, writableBoolean. Default: falsepattern             : Type of test pattern to generateflags: readable, writableEnum "GstVideoTestSrcPattern" Default: 0, "smpte"(0): smpte            - SMPTE 100% color bars(1): snow             - Random (television snow)(2): black            - 100% Black(3): white            - 100% White(4): red              - Red(5): green            - Green(6): blue             - Blue(7): checkers-1       - Checkers 1px(8): checkers-2       - Checkers 2px(9): checkers-4       - Checkers 4px(10): checkers-8       - Checkers 8px(11): circular         - Circular(12): blink            - Blink(13): smpte75          - SMPTE 75% color bars(14): zone-plate       - Zone plate(15): gamut            - Gamut checkers(16): chroma-zone-plate - Chroma zone plate(17): solid-color      - Solid color(18): ball             - Moving ball(19): smpte100         - SMPTE 100% color bars(20): bar              - Bar(21): pinwheel         - Pinwheel(22): spokes           - Spokes(23): gradient         - Gradient(24): colors           - Colorstimestamp-offset    : An offset added to timestamps set on buffers (in ns)flags: readable, writableInteger64. Range: 0 - 9223372036854775807 Default: 0 is-live             : Whether to act as a live sourceflags: readable, writableBoolean. Default: falsek0                  : Zoneplate zero order phase, for generating plain fields or phase offsetsflags: readable, writableInteger. Range: -2147483648 - 2147483647 Default: 0 kx                  : Zoneplate 1st order x phase, for generating constant horizontal frequenciesflags: readable, writableInteger. Range: -2147483648 - 2147483647 Default: 0 ky                  : Zoneplate 1st order y phase, for generating contant vertical frequenciesflags: readable, writableInteger. Range: -2147483648 - 2147483647 Default: 0 kt                  : Zoneplate 1st order t phase, for generating phase rotation as a function of timeflags: readable, writableInteger. Range: -2147483648 - 2147483647 Default: 0 kxt                 : Zoneplate x*t product phase, normalised to kxy/256 cycles per vertical pixel at width/2 from originflags: readable, writableInteger. Range: -2147483648 - 2147483647 Default: 0 kyt                 : Zoneplate y*t product phaseflags: readable, writableInteger. Range: -2147483648 - 2147483647 Default: 0 kxy                 : Zoneplate x*y product phaseflags: readable, writableInteger. Range: -2147483648 - 2147483647 Default: 0 kx2                 : Zoneplate 2nd order x phase, normalised to kx2/256 cycles per horizontal pixel at width/2 from originflags: readable, writableInteger. Range: -2147483648 - 2147483647 Default: 0 ky2                 : Zoneplate 2nd order y phase, normailsed to ky2/256 cycles per vertical pixel at height/2 from originflags: readable, writableInteger. Range: -2147483648 - 2147483647 Default: 0 kt2                 : Zoneplate 2nd order t phase, t*t/256 cycles per pictureflags: readable, writableInteger. Range: -2147483648 - 2147483647 Default: 0 xoffset             : Zoneplate 2nd order products x offsetflags: readable, writableInteger. Range: -2147483648 - 2147483647 Default: 0 yoffset             : Zoneplate 2nd order products y offsetflags: readable, writableInteger. Range: -2147483648 - 2147483647 Default: 0 foreground-color    : Foreground color to use (big-endian ARGB)flags: readable, writable, controllableUnsigned Integer. Range: 0 - 4294967295 Default: 4294967295 background-color    : Background color to use (big-endian ARGB)flags: readable, writable, controllableUnsigned Integer. Range: 0 - 4294967295 Default: 4278190080 horizontal-speed    : Scroll image number of pixels per frame (positive is scroll to the left)flags: readable, writableInteger. Range: -2147483648 - 2147483647 Default: 0 animation-mode      : For pattern=ball, which counter defines the position of the ball.flags: readable, writableEnum "GstVideoTestSrcAnimationMode" Default: 0, "frames"(0): frames           - frame count(1): wall-time        - wall clock time(2): running-time     - running timemotion              : For pattern=ball, what motion the ball doesflags: readable, writableEnum "GstVideoTestSrcMotionType" Default: 0, "wavy"(0): wavy             - Ball waves back and forth, up and down(1): sweep            - 1 revolution per second(2): hsweep           - 1/2 revolution per second, then reset to topflip                : For pattern=ball, invert colors every second.flags: readable, writableBoolean. Default: false

从所有信息中可以看到这个插件只有src，其次输出格式是 video/x-raw数据。

Pad Templates:SRC template: 'src'Availability: AlwaysCapabilities:video/x-rawPads:SRC: 'src'Pad Template: 'src'

从测试命令中我们可以看到gst-launch-1.0 videotestsrc pattern=ball ! xvimagesink，pattern参数，这个也在详细信息中有一一列举。

pattern             : Type of test pattern to generateflags: readable, writableEnum "GstVideoTestSrcPattern" Default: 0, "smpte"(0): smpte            - SMPTE 100% color bars(1): snow             - Random (television snow)(2): black            - 100% Black(3): white            - 100% White(4): red              - Red(5): green            - Green(6): blue             - Blue(7): checkers-1       - Checkers 1px(8): checkers-2       - Checkers 2px(9): checkers-4       - Checkers 4px(10): checkers-8       - Checkers 8px(11): circular         - Circular(12): blink            - Blink(13): smpte75          - SMPTE 75% color bars(14): zone-plate       - Zone plate(15): gamut            - Gamut checkers(16): chroma-zone-plate - Chroma zone plate(17): solid-color      - Solid color(18): ball             - Moving ball(19): smpte100         - SMPTE 100% color bars(20): bar              - Bar(21): pinwheel         - Pinwheel(22): spokes           - Spokes(23): gradient         - Gradient(24): colors           - Colors