Initialization Fragment Found After Media Fragments Unable To Download

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Aleski Fenstermacher

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Jul 22, 2024, 2:52:14 PM7/22/24

to guidopassba

However I don't see the video fragment in the directory. I can only see the tearsofsteel 4k-amidG4XFqDY.mp4.part while file being downloaded and tearsofsteel 4k-amidG4XFqDY.mp4 after download is complete. I can not see individual fragments saved in the directory.

initialization fragment found after media fragments unable to download

Download File ✫ https://urllie.com/2zFPMu

Provide the URL (containing the encrypted session token) for the HLS master playlist to a media player that supports the HLS protocol. Kinesis Video Streams makes the HLS media playlist, initialization fragment, and media fragments available through the master playlist URL. The initialization fragment contains the codec private data for the stream, and other data needed to set up the video or audio decoder and renderer. The media fragments contain H.264-encoded video frames or AAC-encoded audio samples.

GetHLSMediaPlaylist: Retrieves an HLS media playlist, which contains a URL to access the MP4 initialization fragment with the GetMP4InitFragment action, and URLs to access the MP4 media fragments with the GetMP4MediaFragment actions. The HLS media playlist also contains metadata about the stream that the player needs to play it, such as whether the PlaybackMode is LIVE or ON_DEMAND. The HLS media playlist is typically static for sessions with a PlaybackType of ON_DEMAND. The HLS media playlist is continually updated with new fragments for sessions with a PlaybackType of LIVE. There is a distinct HLS media playlist for the video track and the audio track (if applicable) that contains MP4 media URLs for the specific track.

GetMP4InitFragment: Retrieves the MP4 initialization fragment. The media player typically loads the initialization fragment before loading any media fragments. This fragment contains the "fytp" and "moov" MP4 atoms, and the child atoms that are needed to initialize the media player decoder.

The initialization fragment does not correspond to a fragment in a Kinesis video stream. It contains only the codec private data for the stream and respective track, which the media player needs to decode the media frames.

GetMP4MediaFragment: Retrieves MP4 media fragments. These fragments contain the "moof" and "mdat" MP4 atoms and their child atoms, containing the encoded fragment's media frames and their timestamps.

For the HLS streaming session, in-track codec private data (CPD) changes are supported. After the first media fragment is made available in a streaming session, fragments can contain CPD changes for each track. Therefore, the fragments in a session can have a different resolution, bit rate, or other information in the CPD without interrupting playback. However, any change made in the track number or track codec format can return an error when those different media fragments are loaded. For example, streaming will fail if the fragments in the stream change from having only video to having both audio and video, or if an AAC audio track is changed to an ALAW audio track. For each streaming session, only 500 CPD changes are allowed.

Specifies which format should be used for packaging the media. Specifying the FRAGMENTED_MP4 container format packages the media into MP4 fragments (fMP4 or CMAF). This is the recommended packaging because there is minimal packaging overhead. The other container format option is MPEG_TS. HLS has supported MPEG TS chunks since it was released and is sometimes the only supported packaging on older HLS players. MPEG TS typically has a 5-25 percent packaging overhead. This means MPEG TS typically requires 5-25 percent more bandwidth and cost than fMP4.

Media players typically build a timeline of media content to play, based on the timestamps of each fragment. This means that if there is any overlap or gap between fragments (as is typical if HLSFragmentSelector is set to SERVER_TIMESTAMP), the media player timeline will also have small gaps between fragments in some places, and will overwrite frames in other places. Gaps in the media player timeline can cause playback to stall and overlaps can cause playback to be jittery. When there are discontinuity flags between fragments, the media player is expected to reset the timeline, resulting in the next fragment being played immediately after the previous fragment.

ON_DISCONTINUITY: a discontinuity marker is placed between fragments that have a gap or overlap of more than 50 milliseconds. For most playback scenarios, it is recommended to use a value of ON_DISCONTINUITY so that the media player timeline is only reset when there is a significant issue with the media timeline (e.g. a missing fragment).

When there are a higher number of fragments available in a live HLS media playlist, video players often buffer content before starting playback. Increasing the buffer size increases the playback latency, but it decreases the likelihood that rebuffering will occur during playback. We recommend that a live HLS media playlist have a minimum of 3 fragments and a maximum of 10 fragments.

LIVE : For sessions of this type, the HLS media playlist is continually updated with the latest fragments as they become available. We recommend that the media player retrieve a new playlist on a one-second interval. When this type of session is played in a media player, the user interface typically displays a "live" notification, with no scrubber control for choosing the position in the playback window to display.

In LIVE mode, the newest available fragments are included in an HLS media playlist, even if there is a gap between fragments (that is, if a fragment is missing). A gap like this might cause a media player to halt or cause a jump in playback. In this mode, fragments are not added to the HLS media playlist if they are older than the newest fragment in the playlist. If the missing fragment becomes available after a subsequent fragment is added to the playlist, the older fragment is not added, and the gap is not filled.

LIVE_REPLAY : For sessions of this type, the HLS media playlist is updated similarly to how it is updated for LIVE mode except that it starts by including fragments from a given start time. Instead of fragments being added as they are ingested, fragments are added as the duration of the next fragment elapses. For example, if the fragments in the session are two seconds long, then a new fragment is added to the media playlist every two seconds. This mode is useful to be able to start playback from when an event is detected and continue live streaming media that has not yet been ingested as of the time of the session creation. This mode is also useful to stream previously archived media without being limited by the 1,000 fragment limit in the ON_DEMAND mode.

ON_DEMAND : For sessions of this type, the HLS media playlist contains all the fragments for the session, up to the number that is specified in MaxMediaPlaylistFragmentResults. The playlist must be retrieved only once for each session. When this type of session is played in a media player, the user interface typically displays a scrubber control for choosing the position in the playback window to display.

In all playback modes, if FragmentSelectorType is PRODUCER_TIMESTAMP, and if there are multiple fragments with the same start timestamp, the fragment that has the largest fragment number (that is, the newest fragment) is included in the HLS media playlist. The other fragments are not included. Fragments that have different timestamps but have overlapping durations are still included in the HLS media playlist. This can lead to unexpected behavior in the media player.

When FragmentSelectorType is set to PRODUCER_TIMESTAMP and GetHLSStreamingSessionURLInput$PlaybackMode is ON_DEMAND or LIVE_REPLAY, the first fragment ingested with a producer timestamp within the specified FragmentSelector$TimestampRange is included in the media playlist. In addition, the fragments with producer timestamps within the TimestampRange ingested immediately following the first fragment (up to the GetHLSStreamingSessionURLInput$MaxMediaPlaylistFragmentResults value) are included.

Fragments that have duplicate producer timestamps are deduplicated. This means that if producers are producing a stream of fragments with producer timestamps that are approximately equal to the true clock time, the HLS media playlists will contain all of the fragments within the requested timestamp range. If some fragments are ingested within the same time range and very different points in time, only the oldest ingested collection of fragments are returned.

When FragmentSelectorType is set to PRODUCER_TIMESTAMP and GetHLSStreamingSessionURLInput$PlaybackMode is LIVE, the producer timestamps are used in the MP4 fragments and for deduplication. But the most recently ingested fragments based on server timestamps are included in the HLS media playlist. This means that even if fragments ingested in the past have producer timestamps with values now, they are not included in the HLS media playlist.

When FragmentSelectorType is set to PRODUCER_TIMESTAMP and GetHLSStreamingSessionURLInput$PlaybackMode is ON_DEMAND or LIVE_REPLAY , the first fragment ingested with a producer timestamp within the specified FragmentSelector$TimestampRange is included in the media playlist. In addition, the fragments with producer timestamps within the TimestampRange ingested immediately following the first fragment (up to the GetHLSStreamingSessionURLInput$MaxMediaPlaylistFragmentResults value) are included.

When FragmentSelectorType is set to PRODUCER_TIMESTAMP and GetHLSStreamingSessionURLInput$PlaybackMode is LIVE , the producer timestamps are used in the MP4 fragments and for deduplication. But the most recently ingested fragments based on server timestamps are included in the HLS media playlist. This means that even if fragments ingested in the past have producer timestamps with values now, they are not included in the HLS media playlist.