Frame accuracy is missing with clipTo

[kousthub97]

Hello,

Configured the Kaltura with mapped mode with below configuration and clipping the video starting from I frame.

location /hlsfps_test
                {

                        vod hls;
                        vod_hls_absolute_master_urls off;
                        vod_hls_absolute_index_urls off;
                        vod_hls_absolute_iframe_urls off;
                        vod_hls_index_file_name_prefix "chunklist_";
                        vod_align_segments_to_key_frames on;
                        vod_manifest_segment_durations_mode accurate;

                        secure_token_types application/vnd.apple.mpegurl application/dash+xml text/xml;
                        secure_token $args;


                        #vod_hls_container_format fmp4;
                        #vod_hls_force_unmuxed_segments on;
                        vod_drm_enabled off;
                        vod_drm_single_key off;
                        

                        add_header Access-Control-Allow-Headers "Origin,Range,Accept-Encoding,Referer,Cache-Control";
                        add_header Access-Control-Expose-Headers "Server,Content-Length,Content-Range,Date";
                        add_header Access-Control-Allow-Methods "GET, HEAD, OPTIONS";
                        add_header Access-Control-Allow-Origin "*";
                }

In order to measure the frame accuracy embedded the frame number using ffmpeg in mp4 file(30fps) below command.

ffmpeg -i Big_Buck_Bunny_720_10s_20MB.mp4 -vf "drawtext=fontfile=Arial.ttf: text='%{frame_num}': start_number=1: x=(w-tw)/2: y=h-(2*lh): fontcolor=black: fontsize=20: box=1: boxcolor=white: boxborderw=5" -r 30 -g 60 -keyint_min 60 -sc_threshold Big_Buck_Bunny_720_10s_20MB_emd.mp4

Below is the JSON file:

  {
"discontinuity": true,
  "playlistType": "vod",
  "durations": [
    6766,
    6766
  ],
  "sequences": [
    {
      "clips": [
        {
          "type": "source",
          "path": "http://127.0.0.1:8080/Big_Buck_Bunny_720_10s_20MB_emb.mp4",
          "clipFrom": 0000,
          "clipTo": 6766,
          "tracks": "v1"
        },
	{
          "type": "source",
          "path": "http://127.0.0.1:8080/Big_Buck_Bunny_720_10s_20MB_emb.mp4",
          "clipFrom": 0000,
          "clipTo": 6766,
          "tracks": "v1"
        }
      ]
    }
  ]
}

When I tried to HLS playback frame 202 having 203 frame and 204 having 205 frame number. This I had verified by collected HLS stream as mp4 and converted mp4 each frame as jpg.

ffmpeg -i "http://127.0.0.1:81/hlsfps_test/jsons/751927.json/master.m3u8" -c copy testbig.mp4
ffmpeg -i ../../../testbig.mp4 -q:v 2 jpg/output_%04d.jpg 

Please find the attached Input and output mp4 file(HLS to mp4).
https://github.com/user-attachments/assets/3b45c355-139f-414c-adb3-e0494ba0506a
https://github.com/user-attachments/assets/de029fac-2ab5-48b8-a042-f003beea8376

Please let me know any more info is required.