Gstreamer将相机视频输入保存到文件返回空文件

Question

我正在尝试保存来自相机的视频输入（也可以是逐帧），我可以像这样显示其输入：

gst-launch-1.0 udpsrc port=50004 ! application/x-rtp,encoding=JPEG,payload=26 ! rtpjpegdepay ! decodebin ! videoconvert ! autovideosink

我想以视频格式或逐帧将此视频保存到文件中。所以我尝试运行

gst-launch-1.0 udpsrc port=50004 ! application/x-rtp,encoding=JPEG,payload=26 ! rtpjpegdepay ! decodebin ! videoconvert ! avimux ! filesink location=video.avi

但是我的 video.avi 文件是空的。我究竟做错了什么？我是 GStreamer 的初学者，我在网上找不到有用的信息，所以我无法弄清楚该管道的每个部分在做什么。

编辑

详细运行我明白了：

Setting pipeline to PAUSED ...
Pipeline is live and does not need PREROLL ...
Setting pipeline to PLAYING ...
New clock: GstSystemClock
/GstPipeline:pipeline0/GstCapsFilter:capsfilter0.GstPad:src: caps = application/x-rtp, encoding=(string)JPEG, payload=(int)26, media=(string)video, clock-rate=(int)90000
/GstPipeline:pipeline0/GstRtpJPEGDepay:rtpjpegdepay0.GstPad:sink: caps = application/x-rtp, encoding=(string)JPEG, payload=(int)26, media=(string)video, clock-rate=(int)90000
/GstPipeline:pipeline0/GstRtpJPEGDepay:rtpjpegdepay0.GstPad:src: caps = image/jpeg, framerate=(fraction)0/1, width=(int)640, height=(int)480
/GstPipeline:pipeline0/GstDecodeBin:decodebin0.GstGhostPad:sink.GstProxyPad:proxypad0: caps = image/jpeg, framerate=(fraction)0/1, width=(int)640, height=(int)480
/GstPipeline:pipeline0/GstDecodeBin:decodebin0/GstTypeFindElement:typefind.GstPad:src: caps = image/jpeg, framerate=(fraction)0/1, width=(int)640, height=(int)480
[INFO]  bitstreamMode 1, chromaInterleave 0, mapType 0, tiled2LinearEnable 0
/GstPipeline:pipeline0/GstDecodeBin:decodebin0/GstImxVpuDecoder:imxvpudecoder0.GstPad:sink: caps = image/jpeg, framerate=(fraction)0/1, width=(int)640, height=(int)480
/GstPipeline:pipeline0/GstDecodeBin:decodebin0/GstTypeFindElement:typefind.GstPad:sink: caps = image/jpeg, framerate=(fraction)0/1, width=(int)640, height=(int)480
/GstPipeline:pipeline0/GstDecodeBin:decodebin0.GstGhostPad:sink: caps = image/jpeg, framerate=(fraction)0/1, width=(int)640, height=(int)480
/GstPipeline:pipeline0/GstDecodeBin:decodebin0/GstImxVpuDecoder:imxvpudecoder0.GstPad:src: caps = video/x-raw, format=(string)I420, width=(int)640, height=(int)480, interlace-mode=(string)progressive, pixel-aspect-ratio=(fraction)1/1, chroma-site=(string)jpeg, colorimetry=(string)bt601, framerate=(fraction)0/1
/GstPipeline:pipeline0/GstVideoConvert:videoconvert0.GstPad:src: caps = video/x-raw, format=(string)I420, width=(int)640, height=(int)480, interlace-mode=(string)progressive, pixel-aspect-ratio=(fraction)1/1, chroma-site=(string)jpeg, colorimetry=(string)bt601, framerate=(fraction)0/1
/GstPipeline:pipeline0/GstVideoConvert:videoconvert0.GstPad:sink: caps = video/x-raw, format=(string)I420, width=(int)640, height=(int)480, interlace-mode=(string)progressive, pixel-aspect-ratio=(fraction)1/1, chroma-site=(string)jpeg, colorimetry=(string)bt601, framerate=(fraction)0/1
/GstPipeline:pipeline0/GstDecodeBin:decodebin0.GstDecodePad:src_0.GstProxyPad:proxypad1: caps = video/x-raw, format=(string)I420, width=(int)640, height=(int)480, interlace-mode=(string)progressive, pixel-aspect-ratio=(fraction)1/1, chroma-site=(string)jpeg, colorimetry=(string)bt601, framerate=(fraction)0/1

Answer 1

我最终可以使用以下命令写入图像流：

gst-launch-1.0 udpsrc port=50004 ! application/x-rtp,encoding=JPEG,payload=26 ! rtpjpegdepay ! matroskamux ! filesink location=video.mkv

Answer 2

"encoding=JPEG" 只是在流水线的那个阶段指定 jpeg，但稍后由 decodebin 解码，从而产生未压缩的原始视频。

您可以检查您的 gstreamer 安装支持哪些编码器

gst-inspect-1.0 | grep enc

这也列出了音频编码器。可能您必须安装额外的 gstreamer 包才能获得任何或更多编码器，例如 gstreamer1.0-plugins-bad 或 gstreamer1.0-plugins-ugly（此包包含 x264enc）。

然后再次尝试来自@Alper 的管道：

gst-launch-1.0 udpsrc port=50004 ! application/x-rtp,encoding=JPEG,payload=26 ! rtpjpegdepay \
! decodebin ! videoconvert ! x264enc ! avimux ! filesink location=video.avi