broken snippet generation and outputting something that looks like hls

1 files changed, 40 insertions, 9 deletions

diff --git a/remuxer/src/snippet.rs b/remuxer/src/snippet.rs
index 186be19..f23e19e 100644
--- a/remuxer/src/snippet.rs
+++ b/remuxer/src/snippet.rs
@@ -4,18 +4,49 @@
     Copyright (C) 2023 metamuffin <metamuffin.org>
 */
 
-use crate::ebml_track_entry;
-use crate::segment_extractor::SegmentExtractIter;
-use crate::{ebml_header, ebml_segment_info};
-use anyhow::anyhow;
-use anyhow::Context;
+use crate::{
+    ebml_header, ebml_segment_info, ebml_track_entry, segment_extractor::SegmentExtractIter,
+};
+use anyhow::{anyhow, Context, Result};
 use jellycommon::{seek_index::SeekIndex, LocalTrack, NodePublic};
 use jellymatroska::{read::EbmlReader, write::EbmlWriter, Master, MatroskaTag};
 use log::{debug, info};
-use std::{fs::File, io::Write, path::PathBuf};
+use std::{fs::File, io::Write, ops::Range, path::PathBuf};
 
 const SNIPPET_LENGTH: f64 = 2.;
 
+pub fn snippet_index(
+    path_base: PathBuf,
+    item: NodePublic,
+    track_sources: &Vec<LocalTrack>,
+    track: usize,
+) -> Result<Vec<Range<f64>>> {
+    let media_info = item.media.as_ref().unwrap();
+    let private = &track_sources[track];
+    let source_path = path_base.join(&private.path);
+    let mut index = File::open(source_path.with_extension(format!("si.{}", private.track)))
+        .context("opening seek index file")?;
+    let index =
+        bincode::decode_from_std_read::<SeekIndex, _, _>(&mut index, bincode::config::standard())?;
+    let average_kf_interval = media_info.duration / index.keyframes.len() as f64;
+    let kf_per_snip = (SNIPPET_LENGTH / average_kf_interval).ceil() as usize;
+    debug!("average keyframe interval: {average_kf_interval}");
+    debug!(" => keyframes per snippet {kf_per_snip}");
+
+    let n_snips = index.keyframes.len().div_ceil(kf_per_snip);
+    Ok((0..n_snips)
+        .map(|i| {
+            let start = index.blocks[index.keyframes[i * kf_per_snip]].pts as f64 / 1000.;
+            let end = index
+                .keyframes
+                .get((i + 1) * kf_per_snip)
+                .map(|i| index.blocks[*i].pts as f64 / 1000.)
+                .unwrap_or(media_info.duration);
+            start..end
+        })
+        .collect())
+}
+
 pub fn write_snippet_into(
     writer: impl Write,
     path_base: PathBuf,
@@ -50,8 +81,8 @@ pub fn write_snippet_into(
     // TODO maybe refactor this to approx. contant time per snippet
     let average_kf_interval = media_info.duration / index.keyframes.len() as f64;
     let kf_per_snip = (SNIPPET_LENGTH / average_kf_interval).ceil() as usize;
-    info!("average keyframe interval: {average_kf_interval}");
-    info!(" => keyframes per snippet {kf_per_snip}");
+    debug!("average keyframe interval: {average_kf_interval}");
+    debug!(" => keyframes per snippet {kf_per_snip}");
 
     let start_block_index = *index
         .keyframes
@@ -79,7 +110,7 @@ pub fn write_snippet_into(
 
     let mut reader = SegmentExtractIter::new(&mut reader, private.track as u64);
 
-    let mut blocks = Vec::new();
+    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 = reader.next()?;