From: Kostya Shishkov <kostya.shishkov@gmail.com>
Date: Fri, 19 Nov 2021 17:31:46 +0000 (+0100)
Subject: implement raw stream seeking
X-Git-Url: https://git.nihav.org/?p=nihav-tool.git;a=commitdiff_plain;h=9ba5cad53d7bdde5c1fbbcf33bcb554a3bfa0b9d

implement raw stream seeking
---

diff --git a/src/demux.rs b/src/demux.rs
index 084d9e7..8a58f2d 100644
--- a/src/demux.rs
+++ b/src/demux.rs
@@ -31,11 +31,62 @@ pub struct RawStreamCtx<'a> {
     pkt:    Box<dyn NAPacketiser + Send>,
     br:     &'a mut ByteReader<'a>,
     pts:    u64,
+    seek:   SeekIndex,
 }
 
 impl<'a> RawStreamCtx<'a> {
     fn new(stream: NAStreamRef, packetiser: Box<dyn NAPacketiser + Send>, br: &'a mut ByteReader<'a>) -> Self {
-        Self { stream, pkt: packetiser, br, pts: 0 }
+        let mut seek = SeekIndex::new();
+        seek.add_stream(0);
+        Self { stream, pkt: packetiser, br, pts: 0, seek }
+    }
+    fn account_for_packet(&mut self, packet: &mut NAPacket) {
+        let pos = self.br.tell() - (self.pkt.bytes_left() as u64);
+        if packet.get_pts().is_none() && packet.get_duration().is_some() {
+            packet.ts.pts = Some(self.pts);
+        }
+        if packet.is_keyframe() {
+            let pts = packet.get_pts().unwrap_or(self.pts);
+            let time = NATimeInfo::ts_to_time(pts, 1000, self.stream.tb_num, self.stream.tb_den);
+            let in_range = if let Some(last) = self.seek.seek_info[0].entries.last() {
+                    last.pts >= pts
+                } else {
+                    false
+                };
+            if !in_range {
+                self.seek.add_entry(0, SeekEntry { time, pts, pos });
+            }
+        }
+        self.pts += packet.get_duration().unwrap_or(0);
+    }
+    fn get_frame(&mut self) -> DemuxerResult<NAPacket> {
+        let mut buf = [0; 1048576];
+        loop {
+            match self.pkt.get_packet(self.stream.clone()) {
+                Ok(Some(mut packet)) => {
+                    self.account_for_packet(&mut packet);
+                    return Ok(packet);
+                },
+                Ok(None) => {},
+                Err(DecoderError::ShortData) => {},
+                _ => return Err(DemuxerError::InvalidData),
+            };
+            match self.br.read_buf_some(&mut buf) {
+                Ok(size) => {
+                    self.pkt.add_data(&buf[..size]);
+                },
+                Err(_) => {
+                    match self.pkt.get_packet(self.stream.clone()) {
+                        Ok(Some(mut packet)) => {
+                            self.account_for_packet(&mut packet);
+                            return Ok(packet);
+                        },
+                        Ok(None) | Err(DecoderError::ShortData) => return Err(DemuxerError::EOF),
+                        _ => return Err(DemuxerError::InvalidData),
+                    };
+                },
+            };
+        }
     }
 }
 
@@ -189,41 +240,7 @@ impl<'a> DemuxerObject<'a> {
                     }
                 }
             },
-            DemuxerObject::RawStream(ref mut ctx) => {
-                let mut buf = [0; 1048576];
-                loop {
-                    match ctx.pkt.get_packet(ctx.stream.clone()) {
-                        Ok(Some(mut packet)) => {
-                            if packet.get_pts().is_none() && packet.get_duration().is_some() {
-                                packet.ts.pts = Some(ctx.pts);
-                            }
-                            ctx.pts += packet.get_duration().unwrap_or(0);
-                            return Ok(packet);
-                        },
-                        Ok(None) => {},
-                        Err(DecoderError::ShortData) => {},
-                        _ => return Err(DemuxerError::InvalidData),
-                    };
-                    match ctx.br.read_buf_some(&mut buf) {
-                        Ok(size) => {
-                            ctx.pkt.add_data(&buf[..size]);
-                        },
-                        Err(_) => {
-                            match ctx.pkt.get_packet(ctx.stream.clone()) {
-                                Ok(Some(mut packet)) => {
-                                    if packet.get_pts().is_none() && packet.get_duration().is_some() {
-                                        packet.ts.pts = Some(ctx.pts);
-                                    }
-                                    ctx.pts += packet.get_duration().unwrap_or(0);
-                                    return Ok(packet);
-                                },
-                                Ok(None) | Err(DecoderError::ShortData) => return Err(DemuxerError::EOF),
-                                _ => return Err(DemuxerError::InvalidData),
-                            };
-                        },
-                    };
-                }
-            },
+            DemuxerObject::RawStream(ref mut ctx) => ctx.get_frame(),
             _ => unreachable!(),
         }
     }
@@ -231,6 +248,45 @@ impl<'a> DemuxerObject<'a> {
         match *self {
             DemuxerObject::Normal(ref mut dmx) => dmx.seek(seek_time),
             DemuxerObject::Raw(ref mut dmx, _, _) => dmx.seek(seek_time),
+            DemuxerObject::RawStream(ref mut ctx) => {
+                if seek_time == NATimePoint::None {
+                    return Err(DemuxerError::SeekError);
+                }
+                if let Some(last) = ctx.seek.seek_info[0].entries.last() {
+                    let in_index = match seek_time {
+                            NATimePoint::None => unreachable!(),
+                            NATimePoint::PTS(pts) => last.pts >= pts,
+                            NATimePoint::Milliseconds(ms) => last.time >= ms,
+                        };
+                    if in_index {
+                        if let Some(result) = ctx.seek.find_pos(seek_time) {
+                            ctx.br.seek(SeekFrom::Start(result.pos))?;
+                            ctx.pts = result.pts;
+                            ctx.pkt.reset();
+                            return Ok(());
+                        }
+                    }
+                }
+                if let Some(last) = ctx.seek.seek_info[0].entries.last() {
+                    ctx.br.seek(SeekFrom::Start(last.pos))?;
+                    ctx.pts = last.pts;
+                    ctx.pkt.reset();
+                }
+                let mut key_pts = 0;
+                while let Ok(pkt) = ctx.get_frame() {
+                    if !pkt.ts.less_than(seek_time) && !pkt.ts.equal(seek_time) {
+                        break;
+                    }
+                    if pkt.is_keyframe() {
+                        key_pts = pkt.get_pts().unwrap_or(0);
+                    }
+                }
+                let result = ctx.seek.find_pos(NATimePoint::PTS(key_pts)).unwrap();
+                ctx.br.seek(SeekFrom::Start(result.pos))?;
+                ctx.pts = result.pts;
+                ctx.pkt.reset();
+                Ok(())
+            },
             _ => Err(DemuxerError::NotImplemented),
         }
     }