1 use nihav_core::demuxers::*;
3 struct GIFDemuxer<'a> {
4 src: &'a mut ByteReader<'a>,
10 impl<'a> GIFDemuxer<'a> {
11 fn new(io: &'a mut ByteReader<'a>) -> Self {
16 pal: Arc::new([0; 1024]),
19 fn skip_blocks(&mut self) -> DemuxerResult<()> {
21 let size = self.src.read_byte()?;
25 self.src.read_skip(usize::from(size))?;
31 impl<'a> DemuxCore<'a> for GIFDemuxer<'a> {
32 fn open(&mut self, strmgr: &mut StreamManager, _seek_index: &mut SeekIndex) -> DemuxerResult<()> {
33 let mut magic = [0; 6];
34 self.src.read_buf(&mut magic)?;
35 validate!(&magic == b"GIF87a" || &magic == b"GIF89a");
36 self.is_87 = &magic == b"GIF87a";
38 let width = usize::from(self.src.read_u16le()?);
39 let height = usize::from(self.src.read_u16le()?);
40 validate!(width > 0 && height > 0);
41 let flags = self.src.read_byte()?;
42 let edata_size = 1 + 2 + if (flags & 0x80) != 0 { 3 << ((flags & 7) + 1) } else { 0 };
43 let mut edata = vec![0; edata_size];
45 self.src.read_buf(&mut edata[1..])?;
46 if (flags & 0x80) != 0 {
47 let mut npal = [0; 1024];
48 for (dpal, spal) in npal.chunks_exact_mut(4).zip(edata[3..].chunks_exact(3)) {
49 dpal[..3].copy_from_slice(spal);
51 self.pal = Arc::new(npal);
55 match self.src.peek_byte() {
58 Err(_err) => return Err(DemuxerError::IOError),
60 let tag = self.src.read_byte()?;
63 validate!(!self.is_87);
64 let subtype = self.src.read_byte()?;
67 let bsize = self.src.read_byte()?;
68 validate!(bsize == 4);
69 let _flags = self.src.read_byte()?;
70 delay = self.src.read_u16le()?;
71 let _clr = self.src.read_byte()?;
75 let bsize = self.src.read_byte()?;
76 validate!(bsize == 11);
77 let mut app_id = [0; 11];
78 self.src.read_buf(&mut app_id)?;
79 if &app_id == b"NETSCAPE2.0" {
80 let bsize = self.src.read_byte()?;
81 validate!(bsize == 3);
82 let b = self.src.read_byte()?;
84 let _nloops = self.src.read_u16le()?;
93 0x2C => unreachable!(),
94 _ => return Err(DemuxerError::NotImplemented),
98 let vhdr = NAVideoInfo::new(width, height, false, PAL8_FORMAT);
99 let vci = NACodecTypeInfo::Video(vhdr);
100 let vinfo = NACodecInfo::new("gif", vci, Some(edata));
101 if strmgr.add_stream(NAStream::new(StreamType::Video, 0, vinfo, u32::from(delay.max(1)), 100, 0)).is_none() {
102 return Err(DemuxerError::MemoryError);
108 fn get_frame(&mut self, strmgr: &mut StreamManager) -> DemuxerResult<NAPacket> {
110 match self.src.read_byte()? {
112 let mut data = vec![0; 10];
114 self.src.read_buf(&mut data[1..])?;
115 if (data[9] & 0x80) != 0 {
116 let cmap_size = 3 << ((data[9] & 7) + 1);
117 data.resize(10 + cmap_size, 0);
118 self.src.read_buf(&mut data[10..])?;
120 let lzw_bits = self.src.read_byte()?;
122 let mut tbuf = [0; 255];
124 let bsize = usize::from(self.src.read_byte()?);
125 data.push(bsize as u8);
129 self.src.read_buf(&mut tbuf[..bsize])?;
130 data.extend_from_slice(&tbuf[..bsize]);
133 let stream = strmgr.get_stream(0).unwrap();
134 let ts = stream.make_ts(Some(self.frameno), None, None);
135 let mut pkt = NAPacket::new(stream, ts, self.frameno == 0, data);
136 pkt.add_side_data(NASideData::Palette(false, self.pal.clone()));
141 self.src.read_byte()?;
144 0x3B => return Err(DemuxerError::EOF),
145 _ => unimplemented!(),
150 fn seek(&mut self, _time: NATimePoint, _seek_index: &SeekIndex) -> DemuxerResult<()> {
151 Err(DemuxerError::NotPossible)
153 fn get_duration(&self) -> u64 { 0 }
156 impl<'a> NAOptionHandler for GIFDemuxer<'a> {
157 fn get_supported_options(&self) -> &[NAOptionDefinition] { &[] }
158 fn set_options(&mut self, _options: &[NAOption]) { }
159 fn query_option_value(&self, _name: &str) -> Option<NAValue> { None }
162 pub struct GIFDemuxerCreator { }
164 impl DemuxerCreator for GIFDemuxerCreator {
165 fn new_demuxer<'a>(&self, br: &'a mut ByteReader<'a>) -> Box<dyn DemuxCore<'a> + 'a> {
166 Box::new(GIFDemuxer::new(br))
168 fn get_name(&self) -> &'static str { "gif" }
177 fn test_gif_demux() {
178 // sample: https://samples.mplayerhq.hu/image-samples/GIF/3D.gif
179 let mut file = File::open("assets/Misc/3D.gif").unwrap();
180 let mut fr = FileReader::new_read(&mut file);
181 let mut br = ByteReader::new(&mut fr);
182 let mut dmx = GIFDemuxer::new(&mut br);
183 let mut sm = StreamManager::new();
184 let mut si = SeekIndex::new();
185 dmx.open(&mut sm, &mut si).unwrap();
188 let pktres = dmx.get_frame(&mut sm);
189 if let Err(e) = pktres {
190 if e == DemuxerError::EOF { break; }
193 let pkt = pktres.unwrap();
194 println!("Got {}", pkt);