Hinting Options

IsoMedia hinting consists in creating special tracks in the file that contain transport protocol specific information and optionally multiplexing information. These tracks are then used by the server to create the actual packets being sent over the network, in other words they provide the server with hints on how to build packets, hence their names `hint tracks`.  
MP4Box supports creation of hint tracks for RTSP servers supporting these such as QuickTime Streaming Server, DarwinStreaming Server or 3GPP-compliant RTSP servers.  
_Note: GPAC streaming tools [rtp output](rtpout) and [rtsp server](rtspout) do not use hint tracks, they use on-the-fly packetization from any media sources, not just MP4_  
    
Options:  
<div markdown class="option">
<a id="hint" data-level="basic">__-hint__</a>: hint the file for RTP/RTSP  
</div>
<div markdown class="option">
<a id="mtu" data-level="basic">__-mtu__</a> (int, default: __1450__): specify RTP MTU (max size) in bytes (this includes 12 bytes RTP header)  
</div>
<div markdown class="option">
<a id="copy" data-level="basic">__-copy__</a>: copy media data to hint track rather than reference (speeds up server but takes much more space)  
</div>
<div markdown class="option">
<a id="multi" data-level="basic">__-multi__</a> `[maxptime]`: enable frame concatenation in RTP packets if possible (with max duration 100 ms or `maxptime` ms if given)  
</div>
<div markdown class="option">
<a id="rate" data-level="basic">__-rate__</a> (int, default: __90000__): specify rtp rate in Hz when no default for payload  
</div>
<div markdown class="option">
<a id="mpeg4" data-level="basic">__-mpeg4__</a>: force MPEG-4 generic payload whenever possible  
</div>
<div markdown class="option">
<a id="latm" data-level="basic">__-latm__</a>: force MPG4-LATM transport for AAC streams  
</div>
<div markdown class="option">
<a id="static" data-level="basic">__-static__</a>: enable static RTP payload IDs whenever possible (by default, dynamic payloads are always used)  
</div>
<div markdown class="option">
<a id="add-sdp" data-level="basic">__-add-sdp__</a> (string): add given SDP string to movie (`string`) or track (`tkID:string`), `tkID` being the track ID or the hint track ID  
</div>
<div markdown class="option">
<a id="no-offset" data-level="basic">__-no-offset__</a>: signal no random offset for sequence number and timestamp (support will depend on server)  
</div>
<div markdown class="option">
<a id="unhint" data-level="basic">__-unhint__</a>: remove all hinting information from file  
</div>
<div markdown class="option">
<a id="group-single" data-level="basic">__-group-single__</a>: put all tracks in a single hint group  
</div>
<div markdown class="option">
<a id="ocr" data-level="basic">__-ocr__</a>: force all MPEG-4 streams to be synchronized (MPEG-4 Systems only)  
</div>
<div markdown class="option">
<a id="rap" data-level="basic">__-rap__</a>: signal random access points in RTP packets (MPEG-4 Systems)  
</div>
<div markdown class="option">
<a id="ts" data-level="basic">__-ts__</a>: signal AU Time Stamps in RTP packets (MPEG-4 Systems)  
</div>
<div markdown class="option">
<a id="size" data-level="basic">__-size__</a>: signal AU size in RTP packets (MPEG-4 Systems)  
</div>
<div markdown class="option">
<a id="idx" data-level="basic">__-idx__</a>: signal AU sequence numbers in RTP packets (MPEG-4 Systems)  
</div>
<div markdown class="option">
<a id="iod" data-level="basic">__-iod__</a>: prevent systems tracks embedding in IOD (MPEG-4 Systems), not compatible with [-isma](#isma)  
</div>