# Transform and Transcode use cases The transcoding use cases show converting or transforming the video streams from one format to another. Before you run the use cases, ensure that you complete the preconditions mentioned in [GStreamer command-line use cases](https://docs.qualcomm.com/doc/80-70029-50/topic/gstreamer-application-use-cases.html). Note The Qualcomm Computer Vision SDK (fcv) engine is currently not supported. ## 1080p to 1080p–rotate (90/180/270) The use case shows the rotation of scenes from a camera by 180 degrees. The rotated image is displayed on a local display device. Note To rotate the video at different angles, use the rotate property from the [qtivtransform](https://docs.qualcomm.com/doc/80-70029-50/topic/qtivtransform.html) plugin. Use the following commands to run the use case on the target device: - Transform the scene running on DSP using Qualcomm Computer Vision SDK (fcv) engine: gst-launch-1.0 -e qtiqmmfsrc name=camsrc video_0::type=video video_1::type=preview ! video/x-raw,format=NV12,width=1920,height=1080,framerate=30/1 ! qtivtransform engine=fcv rotate=180 ! waylandsink fullscreen=true async=false sync=false Copy to clipboard - Transform the scene running on the GPU using OpenGL ES: gst-launch-1.0 -e qtiqmmfsrc name=camsrc video_0::type=video video_1::type=preview ! video/x-raw,format=NV12,width=1920,height=1080,framerate=30/1 ! qtivtransform engine=gles rotate=180 ! waylandsink fullscreen=true async=false sync=false Copy to clipboard The host camera displays the transformed stream. To stop the use case, use **CTRL + C**. The following figure shows the flow of the pipeline execution: Qualcomm Open source qtivtransform waylandsink camsrc **Figure : Pipeline for displaying flipped and downscaled images–camera source** ### Offline 1080p stream to 1080p–rotate (90/180/270) The use case shows the rotation of scenes from a file source by 180 degrees. The rotated scene is displayed on a local display device. Note To rotate the video at different angles, see the rotate property from [qtivtransform](https://docs.qualcomm.com/doc/80-70029-50/topic/qtivtransform.html). Use the following commands to run the use case on the target device: - Transform the scene running on DSP using Qualcomm Computer Vision SDK (fcv) engine: gst-launch-1.0 -e filesrc location=/opt/.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! video/x-raw,format=NV12 ! qtivtransform engine=fcv rotate=180 ! queue ! waylandsink fullscreen=true Copy to clipboard - Transform the scene running on the GPU using OpenGL ES: gst-launch-1.0 -e filesrc location=/opt/.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! video/x-raw,format=NV12 ! qtivtransform engine=gles rotate=180 ! queue ! waylandsink fullscreen=true Copy to clipboard The transformed stream from the file source is displayed. To stop the use case, use **CTRL + C**. The following figure shows the flow of the pipeline execution: Qualcomm Open source GST BIN filesrc qtdemux h264parse v4l2h264dec qtivtransform waylandsink **Figure : Pipeline for 4k stream downscaled to 1080p, and rotated, and displayed–file source** ### 4K to 1080p–rotate (90/180/270) and downscale The use case shows a 4k resolution video stream from a camera downscaled to 1080p and rotated by 180 degrees. The video is then displayed on a local display device. Note To rotate the video at different angles, see the rotate property from [qtivtransform](https://docs.qualcomm.com/doc/80-70029-50/topic/qtivtransform.html). Use the following commands to run the use case on the target device: - Qualcomm Computer Vision SDK (fcv) engine: gst-launch-1.0 -e qtiqmmfsrc name=camsrc video_0::type=video video_1::type=preview ! video/x-raw,format=NV12,width=3840,height=2160,framerate=30/1 ! qtivtransform engine=fcv rotate=180 ! video/x-raw,format=NV12,width=1920,height=1080 ! waylandsink fullscreen=true Copy to clipboard - GLES engine: gst-launch-1.0 -e qtiqmmfsrc name=camsrc video_0::type=video video_1::type=preview ! video/x-raw,format=NV12,width=3840,height=2160,framerate=30/1 ! qtivtransform engine=gles rotate=180 ! video/x-raw,format=NV12,width=1920,height=1080 ! waylandsink fullscreen=true Copy to clipboard The transformed stream from the camera is displayed. To stop the use case, use **CTRL + C**. The following figure shows the flow of the pipeline execution: Qualcomm Open source qtivtransform Waylandsink camsrc **Figure : Pipeline for 4k image downscaled to 1080p, rotated, and displayed–camera source** ### Offline 4K to 1080p–rotate (90/180/270) and downscale The pipeline shows a 4k resolution video stream from a file source downscaled to 1080p and rotated by 180 degrees. The video is then displayed on a local display device. Note To rotate the video at different angles, see the rotate property from [qtivtransform](https://docs.qualcomm.com/doc/80-70029-50/topic/qtivtransform.html). Use the following commands to run the use case on the target device: - Qualcomm Computer Vision SDK (fcv) engine: gst-launch-1.0 -e filesrc location=/opt/<4K_H264/AVC_file>.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! video/x-raw,format=NV12 ! qtivtransform engine=fcv rotate=180 ! video/x-raw,format=NV12,width=1920,height=1080 ! waylandsink fullscreen=true Copy to clipboard - GLES engine: gst-launch-1.0 -e filesrc location=/opt/<4K_H264/AVC_file>.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! video/x-raw,format=NV12 ! qtivtransform engine=gles rotate=180 ! video/x-raw,format=NV12,width=1920,height=1080 ! waylandsink fullscreen=true Copy to clipboard The transformed stream from the file source is displayed. To stop the use case, use **CTRL + C**. The following figure shows the flow of the pipeline execution: Qualcomm Open source GST BIN filesrc qtdemux h264parse v4l2h264dec qtivtransform waylandsink **Figure : Pipeline for 4k stream downscaled to 1080p, and rotated, and displayed–file source** ### 1080p to 1080p–horizontal and vertical flip The use case shows how to flip the scenes of a camera stream horizontally. Note To flip the scenes, in the following commands, replace `flip-horizontal` with `flip-vertical` and vice versa. For more information, see [qtivtransform](https://docs.qualcomm.com/doc/80-70029-50/topic/qtivtransform.html). Use the following commands to run the use case on the target device: - Qualcomm Computer Vision SDK (fcv) engine: gst-launch-1.0 -e qtiqmmfsrc name=camsrc video_0::type=video video_1::type=preview ! video/x-raw,format=NV12,width=1920,height=1080,framerate=30/1 ! qtivtransform engine=fcv flip-horizontal=true ! waylandsink fullscreen=true Copy to clipboard - GLES engine: gst-launch-1.0 -e qtiqmmfsrc name=camsrc video_0::type=video video_1::type=preview ! video/x-raw,format=NV12,width=1920,height=1080,framerate=30/1 ! qtivtransform engine=gles flip-horizontal=true ! waylandsink fullscreen=true Copy to clipboard The transformed stream from a camera is displayed. To stop the use case, use **CTRL + C**. The following figure shows the flow of the pipeline execution: Qualcomm Open source qtivtransform waylandsink camsrc **Figure : Pipeline for displaying flipped and downscaled images–camera source** ### Offline 1080p to 1080p–horizontal and vertical flip The use case shows how to flip scenes horizontally. Note To flip the scenes, in the following commands, replace `flip-horizontal` with `flip-vertical` and vice versa. For more information, see [qtivtransform](https://docs.qualcomm.com/doc/80-70029-50/topic/qtivtransform.html). Use the following commands to run the use case on the target device: - Qualcomm Computer Vision SDK (fcv) engine: gst-launch-1.0 -e filesrc location=/opt/<1080p_H264/AVC_file>.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! video/x-raw,format=NV12 ! qtivtransform engine=fcv flip-horizontal=true ! waylandsink fullscreen=true Copy to clipboard - GLES engine: gst-launch-1.0 -e filesrc location=/opt/<1080p_H264/AVC_file>.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! video/x-raw,format=NV12 ! qtivtransform engine=gles flip-horizontal=true ! waylandsink fullscreen=true Copy to clipboard The transformed stream from a file source is displayed. To stop the use case, use **CTRL + C**. The following figure shows the flow of the pipeline execution: Qualcomm Open source GST BIN filesrc qtdemux h264parse v4l2h264dec qtivtransform waylandsink **Figure : Pipeline for 4k stream downscaled to 1080p, and rotated, and displayed–file source** ### 4K to 1080p–horizontal and vertical flip with downscale The use case shows how to downscale a 4k resolution video stream to 1080p and flip the scenes horizontally. Note To flip the scenes, in the following commands, replace `flip-horizontal` with `flip-vertical` and vice versa. For more information, see [qtivtransform](https://docs.qualcomm.com/doc/80-70029-50/topic/qtivtransform.html). Use the following commands to run the use case on the target device: - Qualcomm Computer Vision SDK (fcv) engine: gst-launch-1.0 -e qtiqmmfsrc name=camsrc video_0::type=video video_1::type=preview ! video/x-raw,format=NV12,width=3840,height=2160,framerate=30/1 ! qtivtransform engine=fcv flip-vertical=true ! video/x-raw,format=NV12,width=1920,height=1080 ! waylandsink fullscreen=true Copy to clipboard - GLES engine: gst-launch-1.0 -e qtiqmmfsrc name=camsrc video_0::type=video video_1::type=preview ! video/x-raw,format=NV12,width=3840,height=2160,framerate=30/1 ! qtivtransform engine=gles flip-vertical=true ! video/x-raw,format=NV12,width=1920,height=1080 ! waylandsink fullscreen=true Copy to clipboard The transformed stream from the camera is displayed. To stop the use case, use **CTRL + C**. The following figure shows the flow of the pipeline execution: Qualcomm Open source qtivtransform waylandsink camsrc **Figure : Pipeline for displaying flipped and downscaled images–camera source** ### Downscale 4K to 1080p and encode to AVC MP4 The use case uses two copies of a 4k resolution video stream. The first copy is encoded and multiplexed to an MP4 file. A second copy is shared with qtivtransform to downscale it to 1080p resolution. The 1080p stream is then encoded and multiplexed to an MP4 file on the device. Use the following commands to run the use case on the target device: - Qualcomm Computer Vision SDK (fcv) engine: Note This use case isn’t supported on the Ubuntu Server. gst-launch-1.0 -e qtiqmmfsrc name=camsrc video_0::type=video video_1::type=preview ! video/x-raw,format=NV12,width=3840,height=2160,framerate=30/1,interlace-mode=progressive,colorimetry=bt601 ! tee name=t_split t_split. ! queue ! v4l2h264enc capture-io-mode=4 output-io-mode=5 ! h264parse ! queue ! mp4mux ! queue ! filesink location=/opt/4k_video.mp4 t_split. ! qtivtransform engine=fcv ! video/x-raw,format=NV12,width=1920,height=1080,framerate=30/1,interlace-mode=progressive,colorimetry=bt601 ! queue ! v4l2h264enc capture-io-mode=4 output-io-mode=5 ! h264parse ! queue ! mp4mux ! queue ! filesink location=/opt/downscaled_1080p_video.mp4 Copy to clipboard - GLES engine: gst-launch-1.0 -e qtiqmmfsrc name=camsrc video_0::type=video video_1::type=preview ! video/x-raw,format=NV12,width=3840,height=2160,framerate=30/1,interlace-mode=progressive,colorimetry=bt601 ! tee name=t_split t_split. ! queue ! v4l2h264enc capture-io-mode=4 output-io-mode=5 ! h264parse ! queue ! mp4mux ! queue ! filesink location=/opt/4k_video.mp4 t_split. ! qtivtransform engine=gles ! video/x-raw,format=NV12,width=1920,height=1080,framerate=30/1,interlace-mode=progressive,colorimetry=bt601 ! queue ! v4l2h264enc capture-io-mode=4 output-io-mode=5 ! h264parse ! queue ! mp4mux ! queue ! filesink location=/opt/downscaled_1080p_video.mp4 Copy to clipboard To stop the use case, use **CTRL + C**. Pull the recorded content from the target device and play content on the Linux host computer. In the terminal of the host computer, run the following command: scp root@:/opt/ Copy to clipboard In the terminal of the host computer, run the following command to pull the file content: scp -r root@[DEVICE IP-ADDR]:/opt/4k_video.mp4 user1@[HOST IP-ADDR]:/workspace Copy to clipboard scp -r root@[DEVICE IP-ADDR]:/opt/downscaled_1080p_video.mp4 user1@[HOST IP-ADDR]:/workspace Copy to clipboard You can play the MP4 files on a media player. The camera stream is displayed. The following figure shows the flow of the pipeline execution: Qualcomm Open source h264parse mp4mux filesink v4l2h264enc v4l2h264enc h264parse mp4mux filesink tee qtivtransform camsrc **Figure : Pipeline for 4k video–encoding and downscaling to 1080p** ### More transform and transcode use cases Run the following use cases on the target device. ## Video transform use cases - 4K@30 AVC → decode → rotate and downscale → 1080p@30 AVC - Qualcomm Computer Vision SDK (fcv) engine: gst-launch-1.0 -e filesrc location=/opt/<4K_H264/AVC_file>.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! video/x-raw,format=NV12 ! qtivtransform engine=fcv rotate=90CCW ! video/x-raw,format=NV12,width=1920,height=1080 ! v4l2h264enc capture-io-mode=4 output-io-mode=5 ! h264parse ! queue ! mp4mux ! queue ! filesink location=/opt/video.mp4 Copy to clipboard - GLES engine: gst-launch-1.0 -e filesrc location=/opt/<4K_H264/AVC_file>.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! video/x-raw,format=NV12 ! qtivtransform engine=gles rotate=90CCW ! video/x-raw,format=NV12,width=1920,height=1080 ! v4l2h264enc capture-io-mode=4 output-io-mode=5 ! h264parse ! queue ! mp4mux ! queue ! filesink location=/opt/video.mp4 Copy to clipboard - 4K@30 AVC → decode → flip and downscale → 1080p@30 AVC - Qualcomm Computer Vision SDK (fcv) engine: gst-launch-1.0 -e filesrc location=/opt/<4K_H264/AVC_file>.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! video/x-raw,format=NV12 ! qtivtransform engine=fcv flip-vertical=true ! video/x-raw,format=NV12,width=1920,height=1080 ! v4l2h264enc capture-io-mode=4 output-io-mode=5 ! h264parse ! queue ! mp4mux ! queue ! filesink location=/opt/video.mp4 Copy to clipboard - GLES engine: gst-launch-1.0 -e filesrc location=/opt/<4K_H264/AVC_file>.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! video/x-raw,format=NV12 ! qtivtransform engine=gles flip-vertical=true ! video/x-raw,format=NV12,width=1920,height=1080 ! v4l2h264enc capture-io-mode=4 output-io-mode=5 ! h264parse ! queue ! mp4mux ! queue ! filesink location=/opt/video.mp4 Copy to clipboard - Video\_qmmf\_Transform\_rotate\_counter\_clockwise\_3840 x 2160 @30fps - Qualcomm Computer Vision SDK (fcv) engine: gst-launch-1.0 -e qtiqmmfsrc ! video/x-raw,format=NV12,width=3840,height=2160,framerate=30/1 ! qtivtransform engine=fcv rotate=90CCW ! queue ! v4l2h264enc capture-io-mode=4 output-io-mode=5 ! h264parse ! queue ! mp4mux ! queue ! filesink location=/opt/video.mp4 Copy to clipboard - GLES engine: gst-launch-1.0 -e qtiqmmfsrc ! video/x-raw,format=NV12,width=3840,height=2160,framerate=30/1 ! qtivtransform engine=gles rotate=90CCW ! queue ! video/x-raw,format=NV12,width=3840,height=2160,framerate=30/1,interlace-mode=progressive,colorimetry=bt601 ! v4l2h264enc capture-io-mode=4 output-io-mode=5 ! h264parse ! queue ! mp4mux ! queue ! filesink location=/opt/video.mp4 Copy to clipboard - Video\_qmmf\_Transform\_scale\_down\_3840 x 2160 @30fps\_to\_1080p - Qualcomm Computer Vision SDK (fcv) engine: gst-launch-1.0 -e qtiqmmfsrc ! video/x-raw,format=NV12,width=3840,height=2160,framerate=30/1 ! qtivtransform engine=fcv ! queue ! video/x-raw,format=NV12,width=1920,height=1080,framerate=30/1,interlace-mode=progressive,colorimetry=bt601 ! v4l2h264enc capture-io-mode=4 output-io-mode=5 ! h264parse ! queue ! mp4mux ! queue ! filesink location=/opt/video.mp4 Copy to clipboard - GLES engine: gst-launch-1.0 -e qtiqmmfsrc ! video/x-raw,format=NV12,width=3840,height=2160,framerate=30/1 ! qtivtransform engine=gles ! queue ! video/x-raw,format=NV12,width=1920,height=1080,framerate=30/1,interlace-mode=progressive,colorimetry=bt601 ! v4l2h264enc capture-io-mode=4 output-io-mode=5 ! h264parse ! queue ! mp4mux ! queue ! filesink location=/opt/video.mp4 Copy to clipboard - Video\_qmmf\_Transform\_flip\_horizontal\_3840 x 2160 @30fps - Qualcomm Computer Vision SDK (fcv) engine: gst-launch-1.0 -e qtiqmmfsrc ! video/x-raw,format=NV12,width=3840,height=2160,framerate=30/1 ! qtivtransform engine=fcv flip-horizontal=true ! video/x-raw,format=NV12,width=3840,height=2160,framerate=30/1,interlace-mode=progressive,colorimetry=bt601 ! v4l2h264enc capture-io-mode=4 output-io-mode=5 ! h264parse ! queue ! mp4mux ! queue ! filesink location=/opt/video_flip_h.mp4 Copy to clipboard - GLES engine: gst-launch-1.0 -e qtiqmmfsrc ! video/x-raw,format=NV12,width=3840,height=2160,framerate=30/1 ! qtivtransform engine=gles flip-horizontal=true ! video/x-raw,format=NV12,width=3840,height=2160,framerate=30/1,interlace-mode=progressive,colorimetry=bt601 ! v4l2h264enc capture-io-mode=4 output-io-mode=5 ! h264parse ! queue ! mp4mux ! queue ! filesink location=/opt/video_flip_h.mp4 Copy to clipboard - Video\_qmmf\_Transform\_flip\_vertical\_3840 x 2160 @30fps - Qualcomm Computer Vision SDK (fcv) engine: gst-launch-1.0 -e qtiqmmfsrc ! video/x-raw,format=NV12,width=3840,height=2160,framerate=30/1 ! qtivtransform engine=fcv flip-vertical=true ! video/x-raw,format=NV12,width=3840,height=2160,framerate=30/1,interlace-mode=progressive,colorimetry=bt601 ! v4l2h264enc capture-io-mode=4 output-io-mode=5 ! h264parse ! queue ! mp4mux ! queue ! filesink location=/opt/video_flip_v.mp4 Copy to clipboard - GLES engine: gst-launch-1.0 -e qtiqmmfsrc ! video/x-raw,format=NV12,width=3840,height=2160,framerate=30/1 ! qtivtransform engine=gles flip-vertical=true ! video/x-raw,format=NV12,width=3840,height=2160,framerate=30/1,interlace-mode=progressive,colorimetry=bt601 ! v4l2h264enc capture-io-mode=4 output-io-mode=5 ! h264parse ! queue ! mp4mux ! queue ! filesink location=/opt/video_flip_v.mp4 Copy to clipboard ## Video transcode use cases - 4K@30 HEVC → decode → 4K@30 AVC encode: gst-launch-1.0 -e filesrc location=/opt/<4K_H265/HEVC_file>.mp4 ! qtdemux ! queue ! h265parse ! v4l2h265dec capture-io-mode=4 output-io-mode=4 ! v4l2h264enc capture-io-mode=4 output-io-mode=5 ! queue ! h264parse ! mp4mux ! queue ! filesink location=/opt/offline_hevc_to_avc.mp4 Copy to clipboard - 4K@30 AVC → decode → 4K@30 HEVC encode: gst-launch-1.0 -e filesrc location=/opt/<4K_H264/AVC_file>.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! v4l2h265enc capture-io-mode=4 output-io-mode=5 ! queue ! h265parse ! mp4mux ! queue ! filesink location="/opt/offline_avc_to_hevc.mp4" Copy to clipboard ## Dynamic cropping using qtivtransform **Single 1080p file stream from which the ROI is cropped** 1. Display the stream: gst-launch-1.0 filesrc location=/opt/.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! queue ! qtivtransform flip-vertical=true crop="<480,270,960,540>" ! waylandsink fullscreen=true Copy to clipboard 2. Encode the stream data: gst-launch-1.0 -e filesrc location=/opt/.mp4 ! qtdemux ! queue ! h264parse ! v4l2h264dec capture-io-mode=4 output-io-mode=4 ! queue ! qtivtransform flip-horizontal=true crop="<480,270,960,540>" ! queue ! video/x-raw,format=NV12,width=1920,height=1080,framerate=30/1,interlace-mode=progressive,colorimetry=bt601 ! v4l2h264enc capture-io-mode=4 output-io-mode=5 ! h264parse ! queue ! mp4mux ! queue ! filesink location=/opt/offline_crop_vtransform.mp4 Copy to clipboard **Single 1080p camera stream from which ROI is cropped** 1. Display the stream: gst-launch-1.0 -e qtiqmmfsrc ! video/x-raw,format=NV12,width=1920,height=1080,framerate=30/1 ! queue ! qtivtransform flip-horizontal=true crop="<480,270,960,540>" ! waylandsink fullscreen=true Copy to clipboard 2. Encode the stream data: gst-launch-1.0 -e qtiqmmfsrc ! video/x-raw,format=NV12,width=1920,height=1080,framerate=30/1 ! qtivtransform flip-horizontal=true crop="<480,270,960,540>" ! queue ! video/x-raw,format=NV12,width=1920,height=1080,framerate=30/1,interlace-mode=progressive,colorimetry=bt601 ! v4l2h264enc capture-io-mode=4 output-io-mode=5 ! h264parse ! queue ! mp4mux ! queue ! filesink location=/opt/cam_crop_vtransform.mp4 Copy to clipboard ## Related information [Video transcoding](https://docs.qualcomm.com/doc/80-70029-50/topic/gst-video-transcode-example.html) Last Published: Apr 02, 2026 [Previous Topic Multi-camera/Multi-client use cases](https://docs.qualcomm.com/bundle/publicresource/80-70029-50/topics/multi-camera-multi-client-use-cases.md) [Next Topic Video playback use cases](https://docs.qualcomm.com/bundle/publicresource/80-70029-50/topics/video-playback-use-cases.md)