Moments¶

While you stream, you can't also scrub back through four hours of VOD to find the good parts. Moments does it live. CroStream watches your chat and your channel events, notices when the energy jumps, and adds a Twitch stream marker at that point. After the stream, the markers are your list of highlights.

It needs no video and no setup beyond logging in to Twitch: it works from what CroStream already receives. It is on by default, and markers are private to you.

How a moment is found¶

CroStream measures your chat in one-second slices and compares what it sees now with what is normal for this stream. A busy chat that stays busy is not a moment; chat suddenly doubling is. It looks at:

• How fast chat is moving (messages) and how many different people are chatting. Ten people spamming is a bigger deal than one person sending ten messages.
• Reactions: how many people are typing things like KEKW, LUL, W, Pog, monkaS or !!!. You can change the words, see Reaction words.
• Emotes in general.
• People yelling: messages in capitals.
• Channel events: raids, bits, gifted subs, hype train levels, big channel point redemptions and the end of a poll or prediction. Each adds a burst to the score that fades over the next minute.

Those add up to one score. When the score climbs past the threshold and peaks, that is a moment. The reason tells you why, in plain words, such as chat 6× busier (45 chatters) · 40 KEKW · raid from Foo (120).

A few things keep it from being noisy:

Because the score is measured against the stream's own normal, it works the same for a chat of 8 and a chat of 800.

Sensitivity¶

Sensitivity sets how big a reaction has to be.

Not sure? Don't guess: Preview each level on a stream you already did and see what it would have marked.

Stream markers¶

At each moment CroStream adds a Twitch stream marker, a bookmark at that point of the broadcast. It is private: only you (and your editors) see markers, never your viewers.

To find them after the stream, open the VOD in Twitch's Highlighter (or the VOD timeline) and look along it. Each marker is there with its text. By default the text is the reason, so a marker reads like chat 6× busier (45 chatters) · 40 KEKW. The Moments page also links straight to each point in the VOD.

The text is set by Marker text. It takes {reason}, {score} and {uptime}, and Twitch keeps the first 140 characters.

Permissions¶

Markers need the channel:manage:broadcast permission. If your login lacks it, moments are still detected and saved, but the marker shows Marker failed with a message to log in again. Open the Twitch page, press Log in again and approve. No restart is needed.

Clips¶

Create clips is off by default. Turn it on and CroStream also creates a Twitch clip for each moment (after its capture window), which needs the clips:edit permission (already part of a current login).

Capture windows¶

A marker is only a bookmark, so CroStream adds it the instant a moment is found. A clip is different: it has to hold the good part, and the good part is not always at the moment CroStream notices it.

• Chat reacts after the thing happened. When chat erupts, the funny or impressive thing is already a few seconds behind you.
• Some moments are all aftermath. The good part of a raid is the raid arriving and your reaction to it, not the second before.

So CroStream gives every moment a capture window, the stretch of the stream worth keeping, and waits for the window to end before making the clip. The marker is still immediate; only the clip waits.

The three kinds¶

CroStream sorts each moment into a kind, and each kind has its own window.

A moment counts as an event when the event makes up at least half of its score; otherwise it is a chat reaction.

Stream delay¶

What your viewers see is a few seconds behind what you're doing, and chat reacts to what they see. So when you react to a moment, chat reacts a moment later still. Stream delay (5 seconds by default) is that lag. For chat reactions and manual marks, CroStream moves the window earlier by this much so the clip starts before the thing actually happened. Events don't need it: Twitch stamps them when they happen.

If your stream is delayed more than usual, raise it; Preview and a few real clips will tell you.

Merged windows¶

Moments that overlap, or are within Merge gap (10 seconds) of each other, are merged: one capture covers all of them. A raid, followed by chat going wild at the raiders, makes one clip, not two, and every moment in the group points at the same clip. Each moment still gets its own marker.

A group can keep growing while it waits, up to 3 minutes in total. After that, the next moment starts a new group.

When the clip is made¶

CroStream waits until the window ends, plus 3 seconds for Twitch to catch up, and then makes the clip. If you have Create clips on, the moment's clip chip says Clip pending until then.

Twitch decides what a clip can hold: 5 to 60 seconds, ending at the moment the clip is made. So what you get depends on the window:

The clip's title is the moment's reason. If Twitch's AutoMod rejects it, CroStream tries once more without a title.

VOD links¶

A moment's VOD link now starts at the window start, so it opens a little before the good part. The Moments page shows the window next to the time, for example 0:51:40 – 0:53:10 · raid aftermath.

If the stream ends while a window is still open, CroStream captures right away when it still can. If Twitch has already ended the stream, the clip is skipped with stream ended before the moment finished. Closing CroStream mid-window skips it with CroStream was closing. The marker and the VOD link are still there.

Saving moments from OBS¶

A Twitch clip is capped at 60 seconds and at Twitch's quality. If you want the whole window, at the quality you record in, CroStream can take it from OBS's replay buffer instead. When a moment's window has played out, CroStream tells OBS to save the replay buffer, cuts exactly the window out of the saved file and puts the result in your media library, in a folder called Moments.

• Any length, up to what your replay buffer holds.
• Recording quality. The video is copied, not re-encoded, so nothing gets worse and it is fast. Cuts start at the nearest keyframe, so a clip can begin a moment before the window.
• Independent of the Twitch clip. You can have both, a Twitch clip to share and a full-quality file to edit.
• It is off by default: turn on Save moments from OBS.

Set it up¶

1. Connect OBS on the OBS Studio page.
2. Turn on OBS's replay buffer. In OBS, open Settings → Output → Replay Buffer and tick Enable Replay Buffer.
3. Make the buffer long enough. Set Maximum Replay Time to at least your longest window. OBS's default is only 20 seconds. With the default windows, 3 to 5 minutes (180 to 300 s) is right: a raid's window is 95 seconds, and merged windows can reach 3 minutes. The Moments panel tells you the exact number it needs.
4. Raise Maximum Memory to match. The buffer is kept in memory, and OBS stops filling it when it reaches Maximum Memory (512 MB by default), however much time you asked for. A rough guide is the bitrate you record at times the seconds you keep, so 5 minutes at 20 Mbps needs about 750 MB.
5. In CroStream, turn on Save moments from OBS.

The buffer has to be running while you stream. The easy way is to leave OBS: start the replay buffer when you go live on (it is by default): if the buffer isn't running when your stream starts, CroStream starts it. You can also start it yourself in OBS, or with Start it on the Moments panel.

The OBS capture card on the Moments panel checks all of this for you: whether OBS is connected, whether the buffer is on and how much it keeps, with a warning such as OBS keeps only the last 20 s, but a moment can need up to 3m 20s and the setting to change.

FFmpeg¶

Cutting needs FFmpeg, a free video tool. CroStream doesn't include it.

• If it's installed, CroStream finds it by itself.
• Windows and Linux: press Download FFmpeg on the Moments panel. It fetches a pinned, checksum-verified LGPL build of about 170 MB, checks it and unpacks it for CroStream only.
• macOS: install it yourself with brew install ffmpeg, then press Check again.
• Your own copy: set OBS: FFmpeg program to the full path of ffmpeg.exe or ffmpeg. Leave it empty to find one automatically.

FFmpeg is free software under the LGPL v3, from ffmpeg.org, built by BtbN. CroStream runs it as a separate program. A downloaded copy lives in CroStream's tools/ffmpeg folder in its state folder; delete that folder to remove it. A downloaded copy shows up in Settings → About as a third-party component.

What happens to OBS's full replay file¶

Saving the buffer makes a full replay file next to your recordings. Once the cut clip is safely in the media library, CroStream deletes that replay, but only if CroStream asked OBS for it, never any other file. Turn on OBS: keep the full replay files to keep them.

If anything goes wrong, the full replay is always kept, and its path is shown on the moment so you can cut it by hand.

Two computers¶

If OBS runs on another computer (a two-PC setup), CroStream can't read OBS's file. OBS still saves the replay there, and the moment shows Saved on the OBS computer with the path, but nothing is cut. To get cut clips, run CroStream on the computer that runs OBS.

What the moment shows¶

Each moment gets an OBS chip beside its Twitch clip chip:

The messages, and what to do:

On the card, FFmpeg problems read The FFmpeg at \<path> can't be used, FFmpeg \<version> is too old; CroStream needs 4.0 or newer, or The downloaded FFmpeg changed on disk, so it isn't used. Download it again. Download problems (network, damaged or full disk) say what happened and can be retried.

The Moments page¶

Open Moments in the sidebar, under Operate, between History and Viewers.

On the left is the list of your streams, newest first, with the time and length, the title and category, and how many moments each has. A stream that is live now has a Live tag. Load more goes further back.

Select a stream to see its moments. For each one:

Watch VOD at the top of the stream opens the whole VOD. The trash icon deletes a moment from CroStream (Delete this moment?). The marker stays on Twitch.

At the top, Mark a moment marks the current second by hand (it needs you to be live) and, while live, a Heat chip shows how close chat is to a moment right now.

Statuses¶

If the VOD isn't known yet, Time isn't a link. CroStream looks for it again every few minutes, usually after the stream ends and Twitch has made the VOD.

If the page is empty¶

Streams appear once you've been live with History on, and are added to the list as you stream. You will also see these notices at the top:

Preview a past stream¶

Preview replays the detector over a stream you have already done, using the chat and events saved in History. Use it to choose a sensitivity, or to see what Moments would have found before you trust it live.

1. Select a stream on the Moments page.
2. In the Preview panel, choose Low, Medium or High.
3. Press Preview detection.

You get a chart of the score over the stream with the chat volume behind it, and Preview results listing each moment that would have been marked. Nothing is marked on Twitch and nothing is saved; the results are tagged Preview. One that is within 30 seconds of a moment you already have shows already marked. Preview shows the line's threshold, how many chat lines and chatters it read, and Nothing would have been marked with a hint to try a higher sensitivity when a level finds none. Only the first 24 hours of a stream are replayed.

Streams you did before Moments existed work too. CroStream rebuilds them from the viewer counts it recorded and marks them approx: their start and end are estimates, and they have no VOD link. Preview uses the chat saved in History, so it can only be as good as what you kept; if you pruned old chat it has nothing to replay.

The Moments panel¶

Integrations → Moments has the settings and a live panel for use while you stream.

Live detection shows what it is doing: Watching, Rising…, Warming up with the time left, Cooldown with the time left, Limit reached, Offline or Off. The Heat meter fills as chat heats up and a moment is marked when it reaches the line. Beneath it are the count (such as 4 / 30), the score over the last five minutes, Now vs usual (your chat per 10 seconds against its usual level), Recent moments and the same Mark a moment button.

It also warns you about problems, such as a missing permission or History is off, so moments aren't saved.

Settings¶

Save moments from OBS¶

Capture¶

The settings whose names start with Capture: set the windows. Times are in seconds.

Windows are never longer than 3 minutes, and never start before the stream. Settings that can't work, such as an after under 5 seconds, are refused with a message.

React to a moment¶

Moments is also a source of automations.

The Moment detected trigger¶

Add a trigger of type Moment detected to run a macro when a moment is found or marked. It fires after the marker is made, so the marker and VOD link are ready. The clip usually isn't yet, because it waits for the window to end: use Moment captured for that. Moments chooses which: any, auto (the ones CroStream spots) or manual (the ones marked by hand).

Ideas: use {vod_url} in a chat message; to post {clip_url} in Discord, use Moment captured instead, send a chat message "That was a good one", flash the screen, or play a sound.

The Moment captured trigger¶

Moment captured fires once the delayed capture has run, after the window ends, with the clip's result. This is where to react to a clip: "Clip saved!" in chat, or the link in Discord.

Clip from chooses which clip to react to: twitch (the default, so existing triggers behave as before), obs (clips saved from OBS's replay buffer) or any. With any and both on, it fires once for each.

Fire for chooses when it fires: saved (the default) only when the clip was made, or any to also fire when it couldn't be (then {clip_status} is skipped or failed and {clip_error} says why). It has the same variables as Moment detected, with the clip's final {clip_url}, {clip_id} and {clip_status}, plus the window ({window_start}, {window_end}, {window_seconds}) and {kind}. When several moments were merged into one clip, it fires once, for that clip.

For an OBS clip, {target} is obs and {local_path} is the file in the media library, {local_seconds} its length and {local_status} how it went. The other OBS variables are {local_code}, {local_error}, {media_id} and {replay_path} (the full replay, when it was kept).

Example: a macro on Moment captured that sends the chat message Clip saved! {clip_url}. With Fire for left on saved, it only runs when there is a clip to share.

The Mark a moment action¶

The Mark a moment action (in the Moments group) marks the current moment of your stream and saves it on the Moments page. Put it on a hotkey, a Stream Deck button or a chat command such as !mark (set to moderators) so you can bookmark things the detector wouldn't, like a quiet, funny moment.

It gives later steps {moment_id}, {marker_id}, {vod_url}, {clip_url} and {uptime}. Two safeguards:

• It can't loop. Used in a macro that a Moment detected trigger started, it stops with an error, so a moment can never mark another.
• A second press within 10 seconds is ignored and returns the first moment, so a double press on a Stream Deck makes one marker.

You must be live. Its clip covers 45 seconds before to 10 seconds after your press (plus stream delay) unless you change the Manual mark windows. After a hand mark the detector also holds off for the cooldown, so you don't get a second, automatic one for the same beat. Test on the action marks nothing.

Troubleshooting¶

Related¶

• History: where moments are stored, and the chat Preview replays.
• Twitch: the channel:manage:broadcast permission and logging in again.
• Triggers and Macros: react to a moment.
• Media library: where saved OBS clips go, in the Moments folder.
• Hotkeys: mark a moment from the keyboard.
• Events and Actions: every variable.
• Viewers: the ignore list that Moments follows.