| OUTDATED |
| -------- |
| |
| |
| What I propose for EOS condition is th following: As is stands, EOS is a |
| flag in a buffer. However, it's also a signal from an element, which is |
| odd. What I propose is that EOS become a pad thing. Here's how it would |
| work: |
| |
| When a source has a final buffer, it marks it as EOS. It passes this on |
| through the pad, and the pads set a 'pending' EOS state on the way |
| through. When another push or pull happens, only then does the pad signal |
| EOS. This means that EOS doesn't happen until the buffer has passed all |
| the way to the end, and a request for another buffer is starting to work |
| its way back. It gets stopped almost immediately. |
| |
| This gets a bit messy in complex cases, haven't thought them all out. |
| Assuming everything is reasonably symmetric, it should work out cleanly. |
| We may have to add the ability to force buffers to pass even post EOS, but |
| that sounds like a hack. |
| |
| |
| |
| Example: DVD |
| ============ |
| |
| |
| ------------ |-------| |
| -| mpeg2dec |-----| | |
| ------------------------ / ------------ | | |
| | video0|------/ ------------- | | ------------- |
| | | -| subtitle0 |-----| merge |-------| videosink | |
| | subtitle0|------/ ------------- | | ------------- |
| ---------- | | ------------- | | |
| | dvdsrc |---| mpeg2parse subtitle1|--------| subtitle1 |-----| | |
| ---------- | | ------------- |-------| |
| | audio0|--------\ ----------- |----------| |
| | | -| ac3dec0 |-----| | |
| | audio1|-------\ ----------- | | ------------- |
| ------------------------ \ ----------- | switcher |----| audiosink | |
| -| ac3dec1 |-----| | ------------- |
| ----------- |----------| |
| |
| When dvdsrc reads its last buffer, it sets EOS on the buffer and passes it. The pad (probably audio1, |
| since video and audio are interleaved and subtitles don't usually end up at the end of a movie) would |
| set EOS pending, and pass it to mpeg2dec which would pass the EOS to the merge. Merge would then ask |
| for a buffer from subtitle1, since that's the one we're showing subtitles on right now. It would then |
| pull from the mpeg2parse. This would cause a switch back the parser, who's next task is to go and set |
| all the output pads to EOS. It may have to accomplish this by sending a zero-byte buffer. |
| |
| Well, this example isn't actually very good. I'll go ahead and implement it, and we can see what |
| happens. The current setup is so lacking that anything is better.... |
