partial vp9 codec string calculation

1 files changed, 35 insertions, 4 deletions

diff --git a/remuxer/src/codec_param/vp9.rs b/remuxer/src/codec_param/vp9.rs
index f310350..9193607 100644
--- a/remuxer/src/codec_param/vp9.rs
+++ b/remuxer/src/codec_param/vp9.rs
@@ -4,8 +4,11 @@
     Copyright (C) 2026 metamuffin <metamuffin.org>
 */
 
+use log::warn;
 use winter_matroska::TrackEntry;
 
+#[derive(Debug, Clone, Copy)]
+#[repr(u8)]
 enum VPLevel {
     Level1 = 10,
     Level1_1 = 11,
@@ -23,10 +26,11 @@ enum VPLevel {
     Level6_2 = 62,
 }
 
+#[allow(unused)]
 struct VPLevelDef {
     level: VPLevel,
     max_luma_sample_rate: u64,
-    max_luma_picture_size: u32,
+    max_luma_picture_size: u64,
     max_avg_bitrate: f64,
     max_cpb_size: f64,
     min_compression_ratio: f64,
@@ -40,7 +44,7 @@ static LEVELS: &[VPLevelDef] = {
     const fn level(
         a: VPLevel,
         b: u64,
-        c: u32,
+        c: u64,
         d: f64,
         e: f64,
         f: f64,
@@ -80,6 +84,33 @@ static LEVELS: &[VPLevelDef] = {
     ]
 };
 
-pub fn vp9_codec_param(_te: &TrackEntry) -> String {
-    "vp09.00.50.08".to_string()
+fn level_by_characteristic(luma_sample_rate: u64, luma_picture_size: u64) -> VPLevel {
+    for lv in LEVELS {
+        if luma_sample_rate < lv.max_luma_sample_rate
+            && luma_picture_size < lv.max_luma_picture_size
+        {
+            return lv.level;
+        }
+    }
+    warn!("VP9 level out of range");
+    return VPLevel::Level6_2;
+}
+
+pub fn vp9_codec_param(te: &TrackEntry) -> String {
+    if let Some(_cp) = &te.codec_private {
+        todo!()
+    }
+    let Some(video) = te.video.as_ref() else {
+        panic!("vp9 without video tag")
+    };
+
+    let luma_picture_size = video.pixel_width * video.pixel_height;
+    let sample_duration = te.default_duration.map_or(1. / 60., |x| 1e9 / x as f64);
+    let luma_sample_rate = ((luma_picture_size as f64) / sample_duration) as u64;
+
+    let profile = 0; // TODO
+    let level = level_by_characteristic(luma_sample_rate, luma_picture_size);
+    let bit_depth = 8; // TODO
+
+    format!("vp09.{:02}.{:02}.{:02}", profile, level as u8, bit_depth)
 }