On the server side, several components are started, stopped and joined.
Extract an interface to handle them generically.
This will help to support both encoded and raw audio stream, because
they will be two different concrete components, but implementing the
same interface.
PR #3757 <https://github.com/Genymobile/scrcpy/pull/3757>
Expose an option to add a buffering delay (in milliseconds) before
playing audio.
This is similar to the options --display-buffer and --v4l2-buffer for
video frames.
PR #3757 <https://github.com/Genymobile/scrcpy/pull/3757>
Play the decoded audio using SDL.
The audio player frame sink receives the audio frames, resample them
and write them to a byte buffer (introduced by this commit).
On SDL audio callback (from an internal SDL thread), copy samples from
this byte buffer to the SDL audio buffer.
The byte buffer is protected by the SDL_AudioDeviceLock(), but it has
been designed so that the producer and the consumer may write and read
in parallel, provided that they don't access the same slices of the
ring-buffer buffer.
PR #3757 <https://github.com/Genymobile/scrcpy/pull/3757>
Co-authored-by: Simon Chan <1330321+yume-chan@users.noreply.github.com>
A delay buffer delayed all the frames except the first one, to open the
scrcpy window immediately and get a picture.
Make this feature optional, so that the delay buffer might also be used
for audio (especially for simulating a high delay for debugging).
PR #3757 <https://github.com/Genymobile/scrcpy/pull/3757>
For clarity, the fields used only when a delay was set were wrapped in
an anonymous structure.
Now that the delay buffer has been extracted to a separate component,
the delay is necessarily set (it may not be 0), so the fields are always
used.
PR #3757 <https://github.com/Genymobile/scrcpy/pull/3757>
The components needing delayed frames (sc_screen and sc_v4l2_sink)
managed a sc_video_buffer instance, which itself embedded a
sc_frame_buffer instance (to keep only the most recent frame).
In theory, these components should not be aware of delaying: they should
just receive AVFrames later, and only handle a sc_frame_buffer.
Therefore, refactor sc_delay_buffer as a frame source (it consumes)
frames) and a frame sink (it produces frames, after some delay), and
plug an instance in the pipeline only when a delay is requested.
This also removes the need for a specific sc_video_buffer.
PR #3757 <https://github.com/Genymobile/scrcpy/pull/3757>
There was a frame sink trait, implemented by components able to receive
AVFrames, but each frame source had to manually send frame to sinks.
In order to mutualise sink management, add a frame sink trait.
There was a packet sink trait, implemented by components able to
receive AVPackets, but each packet source had to manually send packets
to sinks.
In order to mutualise sink management, add a packet source trait.
A video buffer had 2 responsibilities:
- handle the frame delaying mechanism (queuing packets and pushing them
after the expected delay);
- keep only the most recent frame (using a sc_frame_buffer).
In order to be able to reuse only the frame delaying mechanism, extract
it to a separate component, sc_delay_buffer.
The video_buffer thread clears the queue once it is stopped, but new
frames might still be pushed asynchronously.
To avoid the problem, do not push any frame once the video_buffer is
stopped.
The packets queued for buffering were wrapped in a dynamically allocated
structure with a "next" field.
To avoid this additional layer of allocation and indirection, use a
VecDeque.
The packets queued for recording were wrapped in a dynamically allocated
structure with a "next" field.
To avoid this additional layer of allocation and indirection, use a
VecDeque.
Since in scrcpy a video packet passed to avcodec_send_packet() is always
a complete video frame, it is sufficient to call avcodec_receive_frame()
exactly once.
In practice, it also works for audio packets: the decoder produces
exactly 1 frame for 1 input packet.
In theory, it is an implementation detail though, so
avcodec_receive_frame() should be called in a loop.
By default, scrcpy mirrors only the video when audio capture fails on
the device. Add an option to force scrcpy to fail if audio is enabled
but does not work.
PR #3757 <https://github.com/Genymobile/scrcpy/pull/3757>
If there is exactly one producer, then it can assume that the remaining
space in the buffer will only increase until it writes something.
This assumption may allow the producer to write to the buffer (up to a
known safe size) without any synchronization mechanism, thus allowing
to read and write different parts of the buffer in parallel.
The producer can then commit the write with a lock held, and update its
knowledge of the safe empty remaining space.
PR #3757 <https://github.com/Genymobile/scrcpy/pull/3757>
When audio capture fails on the device, scrcpy continues mirroring the
video stream. This allows to enable audio by default only when
supported.
However, if an audio configuration occurs (for example the user
explicitly selected an unknown audio encoder), this must be treated as
an error and scrcpy must exit.
PR #3757 <https://github.com/Genymobile/scrcpy/pull/3757>
If no bit-rate is passed, let the server use the default value (8Mbps).
This avoids to define a default value on both sides, and to pass the
default bit-rate as an argument when starting the server.
PR #3757 <https://github.com/Genymobile/scrcpy/pull/3757>
By default, audio is enabled (--no-audio must be explicitly passed to
disable it).
However, some devices may not support audio capture (typically devices
below Android 11, or Android 11 when the shell application is not
foreground on start).
In that case, make the server notify the client to dynamically disable
audio forwarding so that it does not wait indefinitely for an audio
stream.
Also disable audio on unknown codec or missing decoder on the
client-side, for the same reasons.
PR #3757 <https://github.com/Genymobile/scrcpy/pull/3757>
For video streams (at least H.264 and H.265), the config packet
containing SPS/PPS must be prepended to the next packet (the following
keyframe).
For audio streams (at least OPUS), they must not be merged.
PR #3757 <https://github.com/Genymobile/scrcpy/pull/3757>
The client does not use the audio stream if there is no display and no
recording (i.e. only V4L2), so disable audio so that the device does not
attempt to capture it.
PR #3757 <https://github.com/Genymobile/scrcpy/pull/3757>
For OPUS codec, FFmpeg expects the raw extradata, but MediaCodec wraps
it in some structure.
Fix the config packet to send only the raw extradata.
PR #3757 <https://github.com/Genymobile/scrcpy/pull/3757>
Remove USER_ID from ServiceManager, and replace it by a constant in
FakeContext.
This is the same as android.os.Process.ROOT_UID, but this constant has
been introduced in API 29.
PR #3757 <https://github.com/Genymobile/scrcpy/pull/3757>
The Callbacks interface notifies new packets. But in addition, the
screen encoder will need to write headers on start.
We could add a function onStart(), but for simplicity, just remove the
interface, which brings no value, and call the streamer directly.
Refs 87972e2022
On any error, all previously opened sockets must be closed.
Handle these errors in a single catch-block. Currently, there are only 2
sockets, but this will simplify even more with more sockets.
Note: this commit is better displayed with --ignore-space-change (-b).
The recorder opened the target file from the packet sink open()
callback, called by the demuxer. Only then the recorder thread was
started.
One golden rule for the recorder is to never block the demuxer for I/O,
because it would impact mirroring. This rule is respected on recording
packets, but not for the initial recorder opening.
Therefore, start the recorder thread from sc_recorder_init(), open the
file immediately from the recorder thread, then make it wait for the
stream to start (on packet sink open()).
Now that the recorder can report errors directly (rather than making the
demuxer call fail), it is possible to report file opening error even
before the packet sink is open.
The recorder has two initialization phases: one to initialize the
concrete recorder object, and one to open its packet_sink trait.
Initialize mutex and condvar as part of the object initialization.
If there were several packet_sink traits (spoiler: one for video, one
for audio), then the mutex and condvar would still be initialized only
once.
Stop scrcpy on recorder errors.
It was previously indirectly stopped by the demuxer, which failed to
push packets to a recorder in error. Report it directly instead:
- it avoids to wait for the next demuxer call;
- it will allow to open the target file from a separate thread and stop
immediately on any I/O error.
User-friendly error messages are printed on specific configuration
exceptions. In that case, do not print the stacktrace.
Also handle the user-friendly error message directly where the error
occurs, and print multiline messages in a single log call, to avoid
confusing interleaving.
Romain Vimont
