Recherche avancée

Sur d’autres sites (10460)

• ffpmeg extracting frames produces too many images

  7 septembre 2019, par Abishur

  I’m using FFMpeg to extract some png files from a video using the following command :

  ffmpeg -i FILE.mp4 -vf "select=not(mod(n\,75))" -vsync vfr img_%03d.png 

  the source video has a duration of 2898 seconds and a framerate of 25 FPS. This means I should be grabbing a picture every 3 seconds for 966 pictures.

  However, instead I’m getting 1158 pictures. After doing some math I’ve discovered that that is the within 2 pictures of what I would expect if I was grabbing the 75th frame from a 30 FPS video.

  I’ve tried -framerate=25 but it still produces the same amount of pictures. The video does have a variable framerate, however using ffprobe it says that the max FPS is 25.47. So even if it was at the max FPS the whole video then I’d still only expect to see 984 pictures.

  Is there anyway to tell FFMpeg that my source video is only 25 fps ? Or am I missing something obvious ?

• Anomalie #1701 (Fermé) : mauvais tri dans boucles de forum

  27 juin 2011, par cedric -

  Produit la requete normale SELECT forum.date_thread, id_thread, forum.id_thread, forum.id_forum FROM spip_forum AS ’forum’ WHERE (forum.statut = ’publie’) AND (forum.id_parent = 0) GROUP BY id_thread ORDER BY forum.date_thread DESC Je ne vois pas de bug, et si je test j’ai bien une date_thread (...)

• How to Adjust Google TTS SSML to Match Original SRT Timing ?

  2 avril, par Alexandre Silkin

  I have an .srt file where each speech segment is supposed to last a specific duration (e.g., 4 seconds). However, when I generate the speech using Google Text-to-Speech (TTS) with SSML, the resulting audio plays the same segment in a shorter time (e.g., 3 seconds).

  


  I want to adjust the speech rate dynamically in SSML so that each segment matches its original timing. My idea is to use ffmpeg to extract the actual duration of each generated speech segment, then calculate the speech rate percentage as :
generated duration
speech rate = --------------------
original duration

  


  This percentage would then be applied in SSML using the tag, like :
Text to be spoken

  


  How can I accurately measure the duration of each segment using ffmpeg, and what is the best way to apply the correct speech rate in SSML to match the original .srt timing ?

  


  I tried duration and my SSML should look like this :

  


          f.write(f&#x27;\t<p>{break_until_start}{text}<break time="{value["></break></p>\n&#x27;)&#xA;

  


  Code writing the SSML :

  


  text = value['text']
start_time_ms = int(value['start_ms']) # Start time in milliseconds
previous_end_ms = int(subsDict.get(str(int(key) - 1), {}).get('end_ms', 0)) # Get the previous end time
gap_to_fill = max(0, start_time_ms - previous_end_ms)

  


          text = text.replace("&amp;", "&amp;amp;").replace(&#x27;"&#x27;, "&amp;quot;").replace("&#x27;", "&amp;apos;").replace("&lt;", "&amp;lt;").replace(&#xA;            ">", "&amp;gt;")&#xA;&#xA;        break_until_start = f&#x27;<break time="{gap_to_fill}ms"></break>&#x27; if gap_to_fill > 0 else &#x27;&#x27;&#xA;&#xA;        f.write(f&#x27;\t<p>{break_until_start}{text}<break time="{value["></break></p>\n&#x27;)&#xA;&#xA;    f.write(&#x27;\n&#x27;)&#xA;