Add PES frame types and FileSectorReader — foundation for stream refactor

- pes.rs: PesFrame, InputStream, OutputStream traits
- sector.rs: SectorReader now public, added FileSectorReader (ISO = file)
- Foundation for unified DiscStream that handles both disc and ISO

src/lib.rs

@@ -79,26 +79,29 @@ pub mod keydb;
 pub(crate) mod labels;
 pub(crate) mod mpls;
 pub mod mux;
+pub mod pes;
 pub(crate) mod platform;
 pub mod profile;
 pub mod scsi;
-pub(crate) mod sector;
+pub mod sector;
 pub(crate) mod speed;
 pub(crate) mod udf;
 
+pub use drive::capture::{
+    capture_drive_data, mask_bytes, mask_string, CapturedFeature, DriveCapture,
+};
 pub use drive::{find_drive, find_drives, Drive, DriveStatus};
-pub use drive::capture::{DriveCapture, CapturedFeature, capture_drive_data, mask_string, mask_bytes};
 pub use error::{Error, Result};
 pub use event::{Event, EventKind};
 pub use identity::DriveId;
 pub use profile::DriveProfile;
 // Platform trait is pub(crate) -- callers use Drive, not Platform directly
+pub use decrypt::{decrypt_sectors, DecryptKeys};
 pub use disc::{
-    AacsState, AudioStream, Clip, Codec, ColorSpace, ContentFormat, ContentReader, Disc,
-    DiscFormat, DiscTitle, Extent, HdrFormat, KeySource, ScanOptions, Stream, SubtitleStream,
-    VideoStream,
+    AacsState, AudioChannels, AudioStream, Clip, Codec, ColorSpace, ContentFormat,
+    Disc, DiscFormat, DiscTitle, Extent, FrameRate, HdrFormat, KeySource, Resolution, SampleRate,
+    ScanOptions, Stream, SubtitleStream, VideoStream,
 };
-pub use mux::DiscOptions;
 pub use mux::DiscStream;
 pub use mux::IOStream;
 pub use mux::IsoStream;
@@ -108,7 +111,6 @@ pub use mux::NetworkStream;
 pub use mux::NullStream;
 pub use mux::StdioStream;
 pub use mux::{open_input, open_output, parse_url, InputOptions, StreamUrl};
-pub use decrypt::{DecryptKeys, decrypt_sectors};
 pub use scsi::ScsiTransport;
 pub use sector::SectorReader;
 pub use speed::DriveSpeed;

src/pes.rs

@@ -0,0 +1,39 @@
+//! PES frame — the universal intermediate format.
+//!
+//! Every input stream produces PES frames. Every output stream consumes them.
+//! The pipeline just moves frames: input.next_frame() → output.write_frame().
+//!
+//! A PES frame is one unit of elementary stream data: a video frame,
+//! an audio frame, a subtitle packet. It has a track ID, timestamp,
+//! and the raw codec data.
+
+/// One frame of elementary stream data.
+#[derive(Debug, Clone)]
+pub struct PesFrame {
+    /// Track index (0-based, matches StreamInfo track order).
+    pub track: usize,
+    /// Presentation timestamp in nanoseconds.
+    pub pts: i64,
+    /// True if this is a keyframe (IDR for video).
+    pub keyframe: bool,
+    /// Raw elementary stream data (NAL units, audio samples, etc).
+    pub data: Vec<u8>,
+}
+
+/// Input stream — produces PES frames from any source.
+pub trait InputStream {
+    /// Get the next frame. Returns None at end of stream.
+    fn next_frame(&mut self) -> std::io::Result<Option<PesFrame>>;
+
+    /// Stream metadata (tracks, duration, etc).
+    fn info(&self) -> &crate::disc::DiscTitle;
+}
+
+/// Output stream — consumes PES frames to any destination.
+pub trait OutputStream {
+    /// Write one frame.
+    fn write_frame(&mut self, frame: &PesFrame) -> std::io::Result<()>;
+
+    /// Finalize (flush, write index, close).
+    fn finish(&mut self) -> std::io::Result<()>;
+}

src/sector.rs

@@ -7,8 +7,47 @@
 use crate::error::Result;
 
 /// Read 2048-byte sectors from a disc or disc image.
-pub trait SectorReader {
+pub trait SectorReader: Send {
     /// Read `count` sectors starting at `lba` into `buf`.
     /// `buf` must be at least `count * 2048` bytes.
     fn read_sectors(&mut self, lba: u32, count: u16, buf: &mut [u8]) -> Result<usize>;
+
+    /// Total capacity in sectors, if known.
+    fn capacity(&self) -> u32 { 0 }
+}
+
+/// SectorReader backed by a file (ISO image).
+/// Seeks to lba * 2048, reads count * 2048 bytes.
+pub struct FileSectorReader {
+    file: std::io::BufReader<std::fs::File>,
+    capacity: u32,
+}
+
+impl FileSectorReader {
+    pub fn open(path: &str) -> std::io::Result<Self> {
+        let file = std::fs::File::open(path)?;
+        let len = file.metadata()?.len();
+        let capacity = (len / 2048) as u32;
+        Ok(Self {
+            file: std::io::BufReader::with_capacity(4 * 1024 * 1024, file),
+            capacity,
+        })
+    }
+}
+
+impl SectorReader for FileSectorReader {
+    fn read_sectors(&mut self, lba: u32, count: u16, buf: &mut [u8]) -> Result<usize> {
+        use std::io::{Read, Seek, SeekFrom};
+        let offset = lba as u64 * 2048;
+        let bytes = count as usize * 2048;
+        self.file.seek(SeekFrom::Start(offset))
+            .map_err(|e| crate::error::Error::IoError { source: e })?;
+        self.file.read_exact(&mut buf[..bytes])
+            .map_err(|e| crate::error::Error::IoError { source: e })?;
+        Ok(bytes)
+    }
+
+    fn capacity(&self) -> u32 {
+        self.capacity
+    }
 }