diff options
author | reimar <reimar@b3059339-0415-0410-9bf9-f77b7e298cf2> | 2005-09-03 08:58:34 +0000 |
---|---|---|
committer | reimar <reimar@b3059339-0415-0410-9bf9-f77b7e298cf2> | 2005-09-03 08:58:34 +0000 |
commit | 9a684fa55fb45fcde9eede7a44998c1fe44785f8 (patch) | |
tree | 81736325f3517390c95074d96770599bea99b56d /libmpdemux/demux_mpg.c | |
parent | dbe33c933e60f6c5ef59856f66bb3363eaecdf8b (diff) | |
download | mpv-9a684fa55fb45fcde9eede7a44998c1fe44785f8.tar.bz2 mpv-9a684fa55fb45fcde9eede7a44998c1fe44785f8.tar.xz |
faster mpg and much faster gxf demuxing
git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@16370 b3059339-0415-0410-9bf9-f77b7e298cf2
Diffstat (limited to 'libmpdemux/demux_mpg.c')
-rw-r--r-- | libmpdemux/demux_mpg.c | 79 |
1 files changed, 58 insertions, 21 deletions
diff --git a/libmpdemux/demux_mpg.c b/libmpdemux/demux_mpg.c index a04ec2c50b..6bfa09a5f9 100644 --- a/libmpdemux/demux_mpg.c +++ b/libmpdemux/demux_mpg.c @@ -506,33 +506,70 @@ static int demux_mpg_es_fill_buffer(demuxer_t *demux, demux_stream_t *ds){ return 1; } +/** + * \brief discard until 0x100 header and return a filled buffer + * \param b buffer-end pointer + * \param pos current pos in stream, negative since b points to end of buffer + * \param s stream to read from + * \return new position, differs from original pos when eof hit and thus + * b was modified to point to the new end of buffer + */ +static int find_end(unsigned char **b, int pos, stream_t *s) { + register int state = 0xffffffff; + unsigned char *buf = *b; + int start = pos; + int read, unused; + // search already read part + while (state != 0x100 && pos) { + state = state << 8 | buf[pos++]; + } + // continue search in stream + while (state != 0x100) { + register int c = stream_read_char(s); + if (c < 0) break; + state = state << 8 | c; + } + // modify previous header (from 0x1bc or 0x1bf to 0x100) + buf[start++] = 0; + // copy remaining buffer part to current pos + memmove(&buf[start], &buf[pos], -pos); + unused = start + -pos; // -unused bytes in buffer + read = stream_read(s, &buf[unused], -unused); + unused += read; + // fix buffer so it ends at pos == 0 (eof case) + *b = &buf[unused]; + start -= unused; + return start; +} + +/** + * This format usually uses an insane bitrate, which makes this function + * performance-critical! + * Be sure to benchmark any changes with different compiler versions. + */ static int demux_mpg_gxf_fill_buffer(demuxer_t *demux, demux_stream_t *ds) { demux_packet_t *pack; - uint32_t state = (uint32_t)demux->priv; - int pos = 0; - int discard = 0; - unsigned char *buf; - if (demux->stream->eof) - return 0; + int len; demux->filepos = stream_tell(demux->stream); pack = new_demux_packet(STREAM_BUFFER_SIZE); - buf = pack->buffer; - while (pos < STREAM_BUFFER_SIZE) { - register int c = stream_read_char(demux->stream); - if (c < 0) { // EOF - resize_demux_packet(pack, pos); - break; - } - state = state << 8 | c; - if (state == 0x1bc || state == 0x1bf) - discard = 1; - else if (state == 0x100) - discard = 0; - if (!discard) - buf[pos++] = c; + len = stream_read(demux->stream, pack->buffer, STREAM_BUFFER_SIZE); + if (len <= 0) + return 0; + { + register uint32_t state = (uint32_t)demux->priv; + register int pos = -len; + unsigned char *buf = &pack->buffer[len]; + do { + state = state << 8 | buf[pos]; + if (unlikely((state | 3) == 0x1bf)) + pos = find_end(&buf, pos, demux->stream); + } while (++pos); + demux->priv = (void *)state; + len = buf - pack->buffer; } + if (len < STREAM_BUFFER_SIZE) + resize_demux_packet(pack, len); ds_add_packet(ds, pack); - demux->priv = (void *)state; return 1; } |