start remuxer crate rewrite; added matroska demuxer and format detection

1 files changed, 0 insertions, 219 deletions

diff --git a/remuxer/src/fragment.rs b/remuxer/src/fragment.rs
deleted file mode 100644
index 45a671f..0000000
--- a/remuxer/src/fragment.rs
+++ /dev/null
@@ -1,219 +0,0 @@
-/*
-    This file is part of jellything (https://codeberg.org/metamuffin/jellything)
-    which is licensed under the GNU Affero General Public License (version 3); see /COPYING.
-    Copyright (C) 2025 metamuffin <metamuffin.org>
-*/
-
-use crate::{
-    ebml_header, ebml_segment_info, ebml_track_entry,
-    metadata::{matroska_metadata, MatroskaMetadata},
-    seek_index::get_seek_index,
-    segment_extractor::SegmentExtractIter,
-};
-use anyhow::{anyhow, Context, Result};
-use jellymatroska::{read::EbmlReader, write::EbmlWriter, Master, MatroskaTag};
-use log::{debug, info};
-use std::{
-    fs::File,
-    io::{BufReader, BufWriter, Write},
-    ops::Range,
-    path::Path,
-};
-
-const FRAGMENT_LENGTH: f64 = 4.;
-
-pub fn fragment_index(path: &Path, track: u64) -> Result<Vec<Range<f64>>> {
-    let meta = matroska_metadata(path)?;
-    let duration = media_duration(&meta);
-    let force_kf = meta
-        .as_ref()
-        .tracks
-        .as_ref()
-        .unwrap()
-        .entries
-        .iter()
-        .find(|t| t.track_number == track)
-        .unwrap()
-        .track_type
-        == 17;
-
-    let index = get_seek_index(path)?;
-    let index = index
-        .get(&track)
-        .ok_or(anyhow!("seek index track missing"))?;
-
-    let n_kf = if force_kf {
-        index.blocks.len()
-    } else {
-        index.keyframes.len()
-    };
-
-    let average_kf_interval = duration / n_kf as f64;
-    let kf_per_frag = (FRAGMENT_LENGTH / average_kf_interval).ceil() as usize;
-    debug!("average keyframe interval: {average_kf_interval}");
-    debug!(" => keyframes per frag {kf_per_frag}");
-
-    let n_frags = n_kf.div_ceil(kf_per_frag);
-    Ok((0..n_frags)
-        .map(|i| {
-            let start = index.blocks[if force_kf {
-                i * kf_per_frag
-            } else {
-                index.keyframes[i * kf_per_frag]
-            }]
-            .pts as f64
-                / 1000.;
-            let end = if force_kf {
-                let n = (i + 1) * kf_per_frag;
-                if n >= index.blocks.len() {
-                    None
-                } else {
-                    Some(n)
-                }
-            } else {
-                index.keyframes.get((i + 1) * kf_per_frag).copied()
-            }
-            .map(|i| index.blocks[i].pts as f64 / 1000.)
-            .unwrap_or(duration);
-            start..end
-        })
-        .collect())
-}
-
-pub fn write_fragment_into(
-    writer: impl Write,
-    path: &Path,
-    track: u64,
-    webm: bool,
-    title: &str,
-    n: usize,
-) -> anyhow::Result<()> {
-    let meta = matroska_metadata(path)?;
-    let duration = media_duration(&meta);
-    let track_meta = meta
-        .as_ref()
-        .tracks
-        .as_ref()
-        .unwrap()
-        .entries
-        .iter()
-        .find(|t| t.track_number == track)
-        .unwrap();
-    let force_kf = track_meta.track_type == 17;
-
-    info!("writing fragment {n} of {:?} (track {track})", title);
-    let mut output = EbmlWriter::new(BufWriter::new(writer), 0);
-    let mapped = 1;
-    info!("\t- {track} {path:?} ({} => {mapped})", track);
-    // info!("\t    {}", info);
-    let file = File::open(path).context("opening source file")?;
-    let index = get_seek_index(path)?;
-    let index = index
-        .get(&track)
-        .ok_or(anyhow!("track missing 2"))?
-        .to_owned();
-    debug!("\t    seek index: {} blocks loaded", index.blocks.len());
-    let mut reader = EbmlReader::new(BufReader::new(file));
-
-    let n_kf = if force_kf {
-        index.blocks.len()
-    } else {
-        index.keyframes.len()
-    };
-    debug!("{duration} {n_kf}");
-    let average_kf_interval = duration / n_kf as f64;
-    let kf_per_frag = (FRAGMENT_LENGTH / average_kf_interval).ceil() as usize;
-    debug!("average keyframe interval: {average_kf_interval}");
-    debug!(" => keyframes per frag {kf_per_frag}");
-
-    let (start_block_index, end_block_index) = if force_kf {
-        (n * kf_per_frag, (n + 1) * kf_per_frag)
-    } else {
-        (
-            *index
-                .keyframes
-                .get(n * kf_per_frag)
-                .ok_or(anyhow!("fragment index out of range"))?,
-            *index
-                .keyframes
-                .get((n + 1) * kf_per_frag)
-                .unwrap_or(&index.blocks.len()),
-        )
-    };
-    debug!("writing blocks {start_block_index} to {end_block_index}.");
-
-    let start_block = &index.blocks[start_block_index];
-    let last_block_pts = index
-        .blocks
-        .get(end_block_index)
-        .map(|b| b.pts)
-        .unwrap_or((duration * 1000.) as u64);
-
-    output.write_tag(&ebml_header(webm))?;
-    output.write_tag(&MatroskaTag::Segment(Master::Start))?;
-    output.write_tag(&ebml_segment_info(
-        title.to_string(),
-        (last_block_pts - start_block.pts) as f64 / 1000.,
-    ))?;
-    output.write_tag(&MatroskaTag::Tracks(Master::Collected(vec![
-        ebml_track_entry(mapped, track_meta),
-    ])))?;
-
-    reader.seek(start_block.source_off, MatroskaTag::Cluster(Master::Start))?;
-    let mut reader = SegmentExtractIter::new(&mut reader, track);
-
-    {
-        // TODO this one caused fragments to get dropped by MSE for no reason
-        // for i in start_block_index..end_block_index {
-        //     let index_block = &index.blocks[i];
-        //     let (mut block, duration) = reader.next()?;
-
-        //     assert_eq!(index_block.size, block.data.len(), "seek index is wrong");
-
-        //     block.track = 1;
-        //     block.timestamp_off = 0;
-        //     output.write_tag(&MatroskaTag::Cluster(Master::Collected(vec![
-        //         MatroskaTag::Timestamp(index_block.pts - start_block.pts),
-        //         if let Some(duration) = duration {
-        //             MatroskaTag::BlockGroup(Master::Collected(vec![
-        //                 MatroskaTag::BlockDuration(duration),
-        //                 MatroskaTag::Block(block),
-        //             ]))
-        //         } else {
-        //             MatroskaTag::SimpleBlock(block)
-        //         },
-        //     ])))?;
-        // }
-    }
-    {
-        let mut blocks = vec![MatroskaTag::Timestamp(start_block.pts)];
-        for i in start_block_index..end_block_index {
-            let index_block = &index.blocks[i];
-            let (mut block, duration) = reader.next_block()?;
-
-            assert_eq!(index_block.size, block.data.len(), "seek index is wrong");
-
-            block.track = 1;
-            // TODO this does generate overflows sometimes
-            block.timestamp_off = (index_block.pts as i64 - start_block.pts as i64)
-                .try_into()
-                .unwrap();
-            if let Some(duration) = duration {
-                blocks.push(MatroskaTag::BlockGroup(Master::Collected(vec![
-                    MatroskaTag::BlockDuration(duration),
-                    MatroskaTag::Block(block),
-                ])))
-            } else {
-                blocks.push(MatroskaTag::SimpleBlock(block))
-            }
-        }
-        output.write_tag(&MatroskaTag::Cluster(Master::Collected(blocks)))?;
-    }
-    debug!("wrote {} bytes", output.position());
-    Ok(())
-}
-
-fn media_duration(m: &MatroskaMetadata) -> f64 {
-    let info = m.info.as_ref().unwrap();
-    (info.duration.unwrap_or_default() * info.timestamp_scale as f64) / 1_000_000_000.
-}