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--- ffmpeg:video:duration [2025/05/27 18:24] – peter
+++ ffmpeg:video:duration [2025/05/27 18:34] (current) – [By Packet duration_time] peter
@@ Line 22: / Line 22: @@
 <WRAP info>
-**NOTE:**  This returns an estimate of the duration based on the bitrate and size of the file.
+**NOTE:**  This gets the figures directly from ffmpeg.
+  * This returns an estimate of the duration based on the bitrate and size of the file.
 </WRAP>
@@ Line 47: / Line 50: @@
 </code>
-<WRAP info>
+<WRAP important>
-**NOTE:**  This returns the duration of the entire container, and not just the duration of the video.
+**WARNING:**  This returns the duration of the entire container, and not just the duration of the video.
 </WRAP>
@@ Line 60: / Line 63: @@
 <code bash>
-video_pkt_durations=$(ffprobe -v error -select_streams v:$i -skip_frame nokey -show_entries packet=duration_time -of default=nokey=1:noprint_wrappers=1 "input.mkv")
+video_pkt_durations=$(ffprobe -v error -select_streams v:0 -skip_frame nokey -show_entries packet=duration_time -of default=nokey=1:noprint_wrappers=1 "input.mkv")
 sum_video_pkt_duration=0
@@ Line 68: / Line 71: @@
 #echo "Calculating video pkt_duration..."
 for video_pkt_duration in $video_pkt_durations; do
-  sum_video_pkt_duration=$( echo "${sum_video_pkt_duration} + ${video_pkt_duration}" | bc)
+  sum_video_pkt_duration=$(echo "${sum_video_pkt_duration} + ${video_pkt_duration}" | bc)
   (( count_video_pkt_duration++ ))
 done;
-video_duration=$( echo "scale=6; ${sum_video_pkt_duration} " | bc)
+video_duration=$( echo "scale=${precision}; ${sum_video_pkt_duration} " | bc)
 echo "DURATION=${video_duration}"
 echo "VIDEO FRAMES=${count_video_pkt_duration}"
 </code>
+<WRAP info>
+**NOTE:**  This is very accurate but may take a while.
+</WRAP>
+----
+===== Calculate duration using Size and Bitrate =====
+<code bash>
+duration=$( echo "scale=6; (${video_size} * 8) / ${bitrate}" | bc)
+</code>
+----
+===== Calculate duration using Size and Bitrate =====
+<code bash>
+duration = NUMBER_OF_FRAMES / FPS
+</code>
+<WRAP info>
+**NOTE:**  Returns the duration in seconds.
+</WRAP>
 ----