Media tools
Sume media tools by API: trim, filter, captions, frames, inspect, speech-to-text, upscaling, background removal, transitions, and Timeline assembly.
Start with Video editing API limits: Sume media tool caps in one table
Caption a Reel after First Draft: burn once on the final cut
First Draft shifts where every word lands, so burn captions only on the final cut and restyle with source_caption_id. The $0.20 job, errors and corrections.
Bilingual captions crowd a vertical Reel: lay out two lines
Two caption tracks overfill a 9:16 frame. Keep cards short, centre them, and use Sume's caption design limits for words, width and height. Korean needs Hangul.
YouTube Shorts series: pin one caption look for every episode
Shorts series run from 2026-09-23. Omit style and Sume picks one from the text. Pin style, font and design in one config so ten episodes look the same.
Copy space in an AI image: leave room for text, overlay it in code
Ask for empty space in the prompt, check the region with Pillow, and put the headline on top in code, so the text is exact and the picture stays a picture.
Kling motion control job done: a signed Python webhook receiver
Submit a Sume Kling 3.0 motion-control job with mode webhook, then verify the HMAC signature in Python, reject an empty secret and answer fast. Runnable code.
Loop a 30-second music bed under a 3-minute Reel: the body
A short bed can cover a 180-second Reel with soundtrack.loop, duck_db and a fade-out. One Timeline 1.0 body, the 3-minute bill, and the limits to respect.
MAI-Voice-2.1 is not on Sume: make talking clips with Sume TTS
Microsoft MAI-Voice-2.1 launched 2026-10-01 but Sume does not list it. Here is the path that ships: Sume TTS audio, then H3 Max lip sync on a still.
MiniMax H3 Max lip sync API: your first clip in Python
Submit a still and a Sume-hosted audio file to POST /v1/minimax/h3-max/lip-sync, poll the job, and read the result. Python stdlib, with the 5 to 14.8 s rule.
MiniMax H3 lip sync at 2K? Sume offers 480p, 768p and 1080p
MiniMax H3 the video model lists 2K, but Sume's H3 Max lip-sync route stops at 1080p. The three resolutions, their derived per-second prices and how to choose.
MiniMax H3 Max video or H3 Max lip sync: fixing the wrong_tool error
generate_video refuses minimax/h3-max/lip-sync with wrong_tool. Use avatar-image-to-video_create for lip sync, minimax-h3-max for text or image video.
Reddit's 15-second view rule: a lip-sync clip that stays under it
Reddit's Engaged Video Views beta bills videos over 15 s at 15 s. Sume H3 Max lip sync tops out at 14.8 s of audio, so one clip fits. Specs, math and a caveat.
Reel captions in two languages: language hint vs auto-detect
How Sume video captions pick a language and a style: the optional language hint, auto-detect, the Hangul rule that returns 400, and a Korean Reel example.
Shorts episode title card: a 2-second still, then the clip
Open each Shorts episode on a held title still with Timeline 1.0: slot math, the 0.5 s coverage rule, what stills ignore, and one render body you can copy.
Shorts spec sheet against Sume Timeline output: what is confirmed
YouTube lists 3 minutes, 1080p and a 100-character title for Shorts. Sume Timeline renders 1080x1920 by default. A table of what is confirmed and what to check.
Speed up a Reel? Sume has no speed field, so shorten the cut
Sume's trim, filter and timeline docs list no playback-speed control. Here is what to use to hit a Reel or Short length instead, with the exact limits.
Timeline transition_not_frame_aligned: why a 0.01 s fade fails
A Timeline fade under half a frame rounds to zero frames and is refused with transition_not_frame_aligned. How many frames a fade is at 24, 25, 30 and 60 fps.
transition_snapped_to_frame: a 0.3 s fade at 25 fps is 8 frames
Timeline rounds a fade to whole frames and reports transition_snapped_to_frame as a warning, not a failure. What 0.3 s becomes at 24, 25, 30 and 60 fps.
compose_video_has_no_audio: a silent clip under a still on Sume
Timeline compose warns compose_video_has_no_audio and still completes. The output is silent. How to add a voice-over afterward with a Timeline render.
Can a YouTube Short be square? Rendering 1080x1080 in Sume Timeline
YouTube says Shorts can be square or vertical. How to export 1080x1080 from Sume Timeline, what fit does to a 9:16 source, and the 3-minute ceiling.
Reels profile grid crops to 3:4 (1080x1440): check a frame
A Reel cover is center-cropped to 3:4 on the profile grid, per a third-party guide. Pull the frame with Sume video frames and keep faces and titles inside.
Transparent background AI image on Sume: GPT Image 2.5 field
Only the GPT Image 2.5 rows take background on Sume's image route. OpenAI says transparency needs png or webp output. A request and an alpha check in Python.
How to turn an AI image into an og:image link preview in Python
Ideogram 4.5 on Sume makes a 2:1 image at 1K as 1440x720. A Pillow crop to your link-preview size, plus the og:image:alt tag Open Graph asks for.
Can a YouTube Shorts episode run 4 minutes? Split with source_in
No: the Shorts series limit is 180 seconds. Split a long cut into two parts with Sume Timeline audio.source_in and video source_in, one render per part.
AI video upscaler API fields: factor 1.1 to 4 and fast, standard, pro
The Sume Video Upscale request takes upscale_factor from 1.1 to 4, duration_seconds from 1 to 30 and an enhancement_tier. What they do and cost.
Check a Short has sound and picture before adding it to a YouTube show
YouTube asks shows for high-quality video and sound and says no-visuals videos likely will not count. Probe each Short with Sume video inspect first.
Custom thumbnail for each Short in a YouTube series: pull the frame
YouTube lets a Shorts series carry a unique custom thumbnail per Short. Pull the best frame from each render with Sume video frames, then dress it.
Estimate a video render cost before you pay: Sume timeline plan
POST /v1/timeline-1.0/plan returns billable minutes, an estimated cost and a filtergraph summary without a job, a reserve or a media download.
YouTube show banner and backdrop: one has the title, one must not
YouTube wants a 16:9 banner with the show title and a 16:9 backdrop without it. How to make both from one source image with Sume Ideogram 4.5.
Can a YouTube Shorts series episode be square? Render 1080x1080
Yes. YouTube's Shorts series rule says portrait or square, up to 180 seconds. How to render a square episode with Sume Timeline output width, height and fit.
Write a YouTube show description from your episode transcripts
YouTube asks you to set a show's details but lists no required fields. Pull transcripts with Sume video inspect at $0.01 a minute and draft from them.
Video API transitions: six types, one second max, eight in a row
Sume timeline accepts fade, wipeleft, wiperight, slideup, slidedown and dissolve, with a duration of at most 1 second and no more than eight adjacent fades.
Same music under every Shorts episode: Timeline soundtrack settings
Sequential playback means viewers hear episodes back to back. Reuse one music file at one gain and ducking level in every Sume Timeline render of the season.
Upscale a 90-second video with a 30-second cap: trim, upscale, join
Sume Video Upscale takes up to 30 input seconds per job. Cut a 90-second clip into three, upscale each at $0.009 a second and join them. Total about $1.08.
Public URL or media.sume.com: which Sume media tool takes which
Sume video trim and timeline accept only media.sume.com URLs from your workspace. Captions and video upscale take a public HTTPS URL. Import first.
16:9 insert in a 1080x1920 Short: Timeline fit modes compared
In a 1080x1920 Timeline, cover keeps 31.6% of a 16:9 clip's width, contain shrinks it to 608 px tall, stretch distorts it and blur pads it.
720p landscape to a TikTok 9:16 ad: a 405-wide crop misses 540x960
Cropping 16:9 to 9:16 keeps 31.6% of the width. A 1080p source gives about 608x1080 and clears TikTok's 540x960 minimum; 720p gives 405x720 and does not.
Captions for a voiceover: reuse TTS word timings or run STT?
If you generated the voice on Sume, ask for timestamps.words and skip a 1-cent-a-minute STT pass. If the audio is someone else's, run STT. Here is the split.
Music Router rejects duration: ask for a 28-second bed in the prompt
Sume's Music Router rejects duration and duration_seconds. Put the length in the prompt for a 28-second holiday ad bed, and pay $0.125 a track.
Silent AI clip fails caption_no_speech: burn text with cues instead
A clip with no speech fails the Sume caption job with caption_no_speech. Send cues with text, start and end to burn authored overlay text for a Short or ad.
Sume video trim output: libx264, yuv420p, AAC, exact vs keyframe
Exact trim re-encodes with libx264 and yuv420p, audio as AAC; keyframe copies the stream. Neither YouTube's Shorts nor TikTok's ad page names a codec.
Timeline slots must reach within 0.5 s of the voiceover: 24 s example
Lay out Sume Timeline 1.0 for a 24-second voiceover: four 6-second slots from 0, last within 0.5 s of the end. Plan it free, render for $0.10.
Timeline output.fps: omit it, or you may resample and get judder
Timeline takes output.fps of 24, 25, 30 or 60 and warns when it differs from the sources. YouTube Shorts and TikTok ad pages list no frame rate.
Why a voiceover on an AI video clip never lip-syncs
Video models do not lip-sync to TTS or a later voiceover. Per Sume's docs a talking face comes from Fabric, H3 Max Lip Sync or an avatar talking-video job.
One 45-second voiceover into 15 and 30 second cuts with audio split
One Sume timeline-audio split job can slice a 45-second voiceover into a 15-second and a 30-second file for $0.01. Cut on a sentence end.
Korean caption fonts on Sume: why weight-shift needs Pretendard
Sume's weight-shift and korean-ad caption styles animate a font weight axis that only Pretendard has. Other faces keep color and scale emphasis only.
Voiceover longer than your clips: Timeline pads, loops, 0.5 s rule
If the voiceover outruns your clips, Sume Timeline still renders to audio.duration_seconds: short sources pad or loop, and coverage may stop 0.5 s early.
Video inspect on Sume: 8 stills at 768 px and the fast seek option
Sume video inspect returns 8 mid-bin stills at a 768 px long edge by default, up to 24 stills, and a fast seek mode that can land one GOP early.
6-second ad legal line: Sume TTS speed 1.5 and checking word times
A fast legal read tops out at generation_config.speed 1.5 on Sume TTS. Read the word timings to see whether the line fits your 6 seconds, then cut words.