GRC services
GRC (Game Recording) uses libstagefright and the NvMMLite TVMR library for writing recorded video to MP4s.
Error reporting is done using the new /dev/nverpt-ctrl ioctls.
grc:c
This is "nn::grcsrv::IGrcService".
| Cmd | Name | Notes |
|---|---|---|
| 1 | OpenContinuousRecorder | Takes a total of 0x28-bytes of input and a handle, returns an #IContinuousRecorder. |
| 2 | OpenGameMovieTrimmer | Takes an input u64 and a handle, returns an #IGameMovieTrimmer. |
| 3 | [5.0.0+] | Takes a total of 0x8-bytes of input and a handle, returns an #IOffscreenRecorder. |
| 101 | [5.0.0+] | Takes a total of 0x10-bytes of input, returns an #IMovieMaker. |
| 9903 | [5.0.0+] | Takes 8-bytes of input, no output. |
[5.0.0+] OpenContinuousRecorder now takes an additional 0x20-bytes of input.
IContinuousRecorder
This is "nn::grcsrv::IContinuousRecorder".
| Cmd | Name |
|---|---|
| 1 | |
| 2 | |
| 10 | |
| 11 | |
| 12 | |
| 13 | |
| 14 | [5.0.0+] |
[5.0.0+] Cmd11 now takes a total of 0x40-bytes of input.
[8.0.0+] Cmd11/cmd14 no longer take any rawdata input, these now take a type-0x15 input buffer.
IGameMovieTrimmer
This is "nn::grcsrv::IGameMovieTrimmer".
| Cmd | Name |
|---|---|
| 1 | #BeginTrim |
| 2 | #EndTrim |
| 10 | #GetNotTrimmingEvent |
| 20 | #SetThumbnailRgba |
Album uses CreateGameMovieTrimmer, and retries using the cmd in a loop on error 0x8D4 with svcSleepThread(100000000) being used first. Then all 4 of these commands are used in that same func: #SetThumbnailRgba if the input buffer is set, #GetNotTrimmingEvent, #BeginTrim, waits on the event, then #EndTrim and cleanup.
BeginTrim
Takes an input s32 start, a s32 end, and a #GameMovieId, no output.
The two s32s are the start/end timestamps in 0.5s units.
EndTrim
No input, returns an output #GameMovieId.
This just loads the #GameMovieId from state, when available.
GetNotTrimmingEvent
No input, returns an output Event handle with autoclear=false.
SetThumbnailRgba
Takes a type-0x45 input buffer, a s32 width, and a s32 height, no output.
width must be 1280, height must be 720, and the buffer size must be at least 0x384000. After this validation, this just copies the input buffer to state with size 0x384000 and returns 0.
grc:d
This is "nn::grcsrv::IRemoteVideoTransfer".
Added with 6.0.0.
| Cmd | Name | Notes |
|---|---|---|
| 1 | No input/output. | |
| 2 | Takes an input u32 (must be value 0-1) and a type-0x6 output buffer, returns a total of 0x10-bytes of output. |
Cmd1
Begins video stream. This must not be used more than once, even from a different service session: otherwise the sysmodule will assert.
Cmd2
Retrieves stream data, from the video recording being done of the currently running game title. Takes u32 "stream" (0: video, 1: audio), returns u32 (num_frames?), u32 data_size, u64 (start_timestamp?). Video stream writes H.264 NAL units to the output buffer (try ffplay -f h264). Audio stream is PCM16, 2 channels, and sample-rate = 48000Hz. Official code uses buffer size 0x32000 for video, 0x1000 for audio, and multiple threads to read out both streams at the same time.
This will block until data is available. This will hang if there is no game title running which has video capture enabled.
IOffscreenRecorder
This is "nn::grcsrv::IOffscreenRecorder".
This was added with [5.0.0+].
| Cmd | Name | Notes |
|---|---|---|
| 201 | Takes a total of 0x8-bytes of input, returns a total of 0x8-bytes of output. | |
| 202 | Takes a total of 0x8-bytes of input, no output. |
IMovieMaker
This is "nn::grcsrv::IMovieMaker".
This was added with [5.0.0+].
CreateVideoProxy
No input, returns an #IHOSBinderDriver.
SetAlbumShimLibraryVersion
Takes an input u64 ShimLibraryVersion, no output.
OpenOffscreenLayer
Takes an input u64 LayerHandle, returns an output s32 ID.
This gets the ID for the #IHOSBinderDriver returned by #CreateVideoProxy.
CloseOffscreenLayer
Takes an input u64 LayerHandle, no output.
StartOffscreenRecording
Takes an input u64, no output.
Seems to be unused by official user processes, #StartOffscreenRecordingEx is used instead.
AbortOffscreenRecording
Takes an input u64 LayerHandle, no output.
RequestOffscreenRecordingFinishReady
Takes an input u64 LayerHandle, no output.
This is the first cmd used by official sw when finishing recording. Then it waits on the Event originally loaded from #GetOffscreenLayerRecordingFinishReadyEvent. Then CompleteOffscreenRecordingFinishEx* is used, depending on the sdk-nso version. On any errors, #AbortOffscreenRecording is used.
StartOffscreenRecordingEx
Takes an input u64 LayerHandle and an #OffscreenRecordingParameter, no output.
CompleteOffscreenRecordingFinish
Takes an input u64 LayerHandle and a type-0x5 input buffer, no output.
Seems to be unused by official user processes, #CompleteOffscreenRecordingFinishEx0 is used instead.
CompleteOffscreenRecordingFinishEx0
Takes two input s32s width/height, an input u64 LayerHandle and 2 type-0x5 input buffers, no output.
The input buffers are optional, addr=NULL and size=0 can be used for these.
width/height must be 1280x720, these fields are unused afterwards.
Besides width/height, this is the same as #CompleteOffscreenRecordingFinish except the second buffer is user-specified instead of addr=NULL/size=0.
CompleteOffscreenRecordingFinishEx1
Takes two input s32s width/height, an input u64 LayerHandle and two type-0x5 input buffers, returns an output ApplicationAlbumEntry.
Same as #CompleteOffscreenRecordingFinishEx0 except the output struct is returned in the cmdreply.
GetOffscreenLayerError
Takes an input u64 LayerHandle, no output.
EncodeOffscreenLayerAudioSample
Takes an input u64 LayerHandle and a type-0x5 input buffer, returns an output u64 out_size.
Official sw enters a loop for handling the user-specified buffer:
- Waits on the Event originally loaded from #GetOffscreenLayerAudioEncodeReadyEvent.
- Uses the cmd with the current buffer_addr+pos and the remaining_size.
- Updates the current pos and remaining_size with the out_size.
- Repeats the loop until the remaining_size is 0.
GetOffscreenLayerRecordingFinishReadyEvent
Takes an input u64 LayerHandle, returns an output event handle with autoclear disabled.
GetOffscreenLayerAudioEncodeReadyEvent
Takes an input u64 LayerHandle, returns an output event handle with autoclear disabled.
OffscreenRecordingParameter
| Offset | Size | Description | Default value |
|---|---|---|---|
| 0x0 | 0x10 | ? | 0 |
| 0x10 | 0x4 | ? | 0x103 |
| 0x14 | 0x4 | s32 VideoBitRate | 8000000 |
| 0x18 | 0x4 | s32 VideoWidth | 1280 |
| 0x1C | 0x4 | s32 VideoHeight | 720 |
| 0x20 | 0x4 | s32 VideoFrameRate | 30 |
| 0x24 | 0x4 | s32 VideoKeyFrameInterval | 30 |
| 0x28 | 0x4 | s32 AudioBitRate | 128000 ([5.0.0-5.1.0] 1536000) |
| 0x2C | 0x4 | s32 AudioSampleRate | 48000 |
| 0x30 | 0x4 | s32 AudioChannelCount | 2 |
| 0x34 | 0x4 | "nn::audio::SampleFormat" AudioSampleFormat | 2 |
| 0x38 | 0x4 | "nn::album::ImageOrientation" VideoImageOrientation. | 0 |
| 0x3C | 0x44 | ? | 0 |
This is "nn::grcsrv::OffscreenRecordingParameter". This is a 0x80-byte struct. "nn::grc::OffscreenRecordingParameter" and "nn::album::MovieMakerMovieParameter" are identical to this.
The above default values are initialized by the official user-process via sdk-nso funcs "nn::album::MovieMakerMovieParameter::GetDefaultValue()" / "nn::album::MovieMakerMovieParameter::MovieMakerMovieParameter()" (both funcs are identical).
GameMovieId
| Offset | Size | Description |
|---|---|---|
| 0x0 | 0x18 | Same as the last 0x18-bytes of AlbumEntry. |
| 0x18 | 0x28 | Unused, always zero. |
This is "nn::grcsrv::GameMovieId". This is a 0x40-byte struct.
IHOSBinderDriver
This is the same interface as NV IHOSBinderDriver.