{
  "id": "opencv/video-capture-gstreamer-pipeline-error",
  "signature": "[ WARN:0] global /tmp/opencv-4.9.0/modules/videoio/src/cap_gstreamer.cpp (2401) open OpenCV | GStreamer warning: unable to start pipeline",
  "signature_zh": "[ WARN:0] global /tmp/opencv-4.9.0/modules/videoio/src/cap_gstreamer.cpp (2401) open OpenCV | GStreamer 警告: 无法启动管道",
  "regex": "\\[ WARN:0\\] global .*cap_gstreamer\\.cpp \\(2401\\) open OpenCV \\| GStreamer warning: unable to start pipeline",
  "domain": "opencv",
  "category": "runtime_error",
  "subcategory": null,
  "root_cause": "The GStreamer pipeline string provided to VideoCapture is malformed or references a source that does not exist or is not accessible.",
  "root_cause_type": "generic",
  "root_cause_zh": "提供给 VideoCapture 的 GStreamer 管道字符串格式错误，或引用了不存在或无法访问的源。",
  "versions": [
    {
      "version": "4.8.0",
      "introduced": null,
      "deprecated": null,
      "removed": null,
      "behavior_change": null,
      "status": "active"
    },
    {
      "version": "4.9.0",
      "introduced": null,
      "deprecated": null,
      "removed": null,
      "behavior_change": null,
      "status": "active"
    },
    {
      "version": "4.10.0",
      "introduced": null,
      "deprecated": null,
      "removed": null,
      "behavior_change": null,
      "status": "active"
    }
  ],
  "os_specific": {},
  "dead_ends": [
    {
      "action": "Installing GStreamer from source without proper plugins (e.g., missing gst-plugins-good)",
      "why_fails": "Missing plugin packages cause pipeline initialization to fail even if GStreamer core is installed.",
      "fail_rate": 0.8,
      "condition": "",
      "sources": []
    },
    {
      "action": "Using a pipeline string with absolute file paths containing spaces without proper escaping",
      "why_fails": "GStreamer requires spaces in paths to be escaped with single quotes or backslashes; without escaping, the pipeline fails to parse.",
      "fail_rate": 0.9,
      "condition": "",
      "sources": []
    }
  ],
  "workarounds": [
    {
      "action": "Verify the GStreamer pipeline by testing it in terminal first: gst-launch-1.0 filesrc location=/path/to/video.mp4 ! qtdemux ! h264parse ! avdec_h264 ! videoconvert ! appsink. If it fails, install missing plugins: sudo apt-get install gstreamer1.0-plugins-good gstreamer1.0-plugins-bad.",
      "success_rate": 0.9,
      "how": "Verify the GStreamer pipeline by testing it in terminal first: gst-launch-1.0 filesrc location=/path/to/video.mp4 ! qtdemux ! h264parse ! avdec_h264 ! videoconvert ! appsink. If it fails, install missing plugins: sudo apt-get install gstreamer1.0-plugins-good gstreamer1.0-plugins-bad.",
      "condition": "",
      "sources": []
    },
    {
      "action": "Use raw video device pipeline with proper format: cv::VideoCapture cap('v4l2src device=/dev/video0 ! videoconvert ! appsink', cv::CAP_GSTREAMER);",
      "success_rate": 0.85,
      "how": "Use raw video device pipeline with proper format: cv::VideoCapture cap('v4l2src device=/dev/video0 ! videoconvert ! appsink', cv::CAP_GSTREAMER);",
      "condition": "",
      "sources": []
    }
  ],
  "workarounds_zh": [
    "Verify the GStreamer pipeline by testing it in terminal first: gst-launch-1.0 filesrc location=/path/to/video.mp4 ! qtdemux ! h264parse ! avdec_h264 ! videoconvert ! appsink. If it fails, install missing plugins: sudo apt-get install gstreamer1.0-plugins-good gstreamer1.0-plugins-bad.",
    "Use raw video device pipeline with proper format: cv::VideoCapture cap('v4l2src device=/dev/video0 ! videoconvert ! appsink', cv::CAP_GSTREAMER);"
  ],
  "transition_graph": {
    "leads_to": [],
    "preceded_by": [],
    "frequently_confused_with": []
  },
  "official_doc_url": "https://docs.opencv.org/4.x/d0/da7/videoio_overview.html",
  "official_doc_section": null,
  "error_code": null,
  "verification_tier": "ai_generated",
  "confidence": 0.86,
  "fix_success_rate": 0.87,
  "resolvable": "true",
  "first_seen": "2024-09-10",
  "last_confirmed": "2024-06-01",
  "last_updated": "2024-06-01",
  "evidence_count": 1,
  "tags": [],
  "locale": "en",
  "aliases": []
}