Seeed-Studio CV181X/CV182X/CV180X Multimedia Skill
Instructions
Step 1: Confirm the missing context before giving exact API guidance
When the user asks about exact API behavior, limits, struct fields, or error diagnosis, first confirm the available context:
- Target chip or board model
- SDK version or SDK source tree path
- Relevant code snippet, pipeline stage, or runtime log
If required context is missing:
- State that the answer is limited or provisional
- Ask for the specific missing artifact needed to verify the claim
- Do not present SDK-version-specific behavior as universal unless it is confirmed in the available references
Step 2: Prefer authoritative sources
Use the source order already defined in this skill: SDK headers first, SDK samples second, external material only if it is verified against the headers or samples
Complete Reference Index
All 18 reference files with searchable keywords:
| File | Keywords | Key APIs |
|---|---|---|
references/vi.md |
camera, sensor, ISP, MIPI, DEV, PIPE, CHN, video input | CVI_VI_*, CVI_ISP_*, CVI_MIPI_* |
references/vpss.md |
scaling, crop, resize, rotate, cvtColor, format conversion, group, channel | CVI_VPSS_*, SendFrame, GetChnFrame |
references/venc.md |
encode, H.264, H.265, HEVC, JPEG, MJPEG, bitrate, GOP | CVI_VENC_*, SendFrame, GetStream |
references/vdec.md |
decode, JPEG decode, H.264 decode, bitstream | CVI_VDEC_*, SendStream, GetFrame |
references/vb.md |
buffer pool, VB, memory, block, pool sizing, CommonPool | CVI_VB_*, GetBlock, ReleaseBlock |
references/sys.md |
bind, unbind, init, exit, VI_VPSS_MODE, VPSS_MODE | CVI_SYS_*, Bind, SetVIVPSSMode |
references/vo.md |
display, output, LCD, HDMI, layer, framebuffer | CVI_VO_*, SendFrame, ChnShow |
references/rgn.md |
OSD, overlay, region, text, graphics, privacy mask | CVI_RGN_*, AttachToChn, SetBitMap |
references/gdc.md |
distortion, fisheye, LDC, rotation, mesh, warp | CVI_GDC_*, AddCorrectionTask |
references/audio.md |
audio, microphone, speaker, AI, AO, AENC, ADEC, VQE | CVI_AI_*, CVI_AO_*, CVI_AENC_* |
references/ion.md |
ION, DMA, cache, flush, invalidate, physical address | CVI_SYS_IonAlloc, IonFlushCache |
references/debug.md |
/proc, log, debug, status, diagnostics | /proc/cvitek/*, log level |
references/troubleshooting.md |
error, ERR_VPSS_NOBUF, ERR_VB_NOBUF, failure, fix | error codes, solutions |
references/binding-cookbook.md |
concurrent, dual pipeline, online, offline, scenario | multi-scenario design |
references/integration-guide.md |
integration, cross-module, ownership, lifecycle | system design rules |
references/platform.md |
SDK, path, pixel format, CV181X, CV182X, CV180X | platform differences |
references/overview.md |
architecture, workflow, pipeline, introduction | system overview |
references/scenarios.md |
example, surveillance, doorbell, NVR, application | complete examples |
Quick Lookup
By Task
| Task | Reference |
|---|---|
| Camera capture | references/vi.md |
| Video scaling/crop/rotate | references/vpss.md |
| H.264/H.265/JPEG encode | references/venc.md |
| JPEG/H.264 decode | references/vdec.md |
| Buffer pool planning | references/vb.md |
| Module binding | references/sys.md |
| Video display | references/vo.md |
| OSD/overlay | references/rgn.md |
| Fisheye correction | references/gdc.md |
| Audio capture/playback | references/audio.md |
| DMA memory | references/ion.md |
| Debugging | references/debug.md |
| Error diagnosis | references/troubleshooting.md |
By Error Code
| Error | Reference |
|---|---|
ERR_VPSS_NOBUF (0xc006800e) |
references/troubleshooting.md |
ERR_VB_NOBUF |
references/vb.md |
ERR_VENC_NOBUF |
references/venc.md |
ERR_VI_NOTREADY |
references/vi.md |
| Bind failure | references/sys.md |
By Pipeline
| Pipeline | References |
|---|---|
| Camera -> VPSS (online) | vi.md, vpss.md, sys.md |
| File -> VPSS (offline) | vpss.md, vb.md |
| JPEG decode -> VPSS | vdec.md, vpss.md |
| VPSS -> VENC | venc.md, sys.md |
| Dual pipeline | references/binding-cookbook.md |
Private Operating Procedures
1. Authoritative Source Order
- SDK headers in
cvi_mpi/include/ - SDK samples in
cvi_mpi/sample/ - Never: external repos without header verification
2. VPSS Input Ownership
- VPSS group for ONE input type: ISP or MEM
- Never switch between Bind and SendFrame at runtime
- Concurrent ISP + MEM: separate groups and VB pools
3. VI-VPSS Mode Selection
| Mode | Use Case |
|---|---|
VI_OFFLINE_VPSS_ONLINE |
Camera pipeline (recommended) |
VI_OFFLINE_VPSS_OFFLINE |
Maximum flexibility |
VI_ONLINE_VPSS_ONLINE |
Lowest latency |
4. Binding Requirements
- Control plane:
CVI_SYS_Bindestablishes relationship - Data plane: Mode setting determines data flow
- Binding required even in ISP direct mode
- Unbind before stop; bind after start
5. Camera Readiness
- Warm up pipeline after start
- Discard first few frames before capture
6. VENC SendFrame Memory
- Must use VB pool, not raw ION
- Use
CVI_VB_GetBlock(), setframe.u32PoolId
7. Diagnostics
On failure: /proc/cvitek/{sys,vb,vi,vpss,vdec,venc}
Module Init Order
1. CVI_VB_SetConfig + CVI_VB_Init
2. CVI_SYS_Init
3. CVI_SYS_SetVIVPSSMode
4. CVI_SYS_SetVPSSModeEx
5. VI: sensor -> mipi -> dev -> pipe -> isp -> chn
6. VPSS: CreateGrp -> SetChnAttr -> EnableChn -> StartGrp
7. CVI_SYS_Bind
8. Warmup
VPSS Mode Reference
VPSS_MODE_DUAL
DEV0 = VPSS_INPUT_MEM -> Offline (SendFrame)
DEV1 = VPSS_INPUT_ISP -> Camera (Bind)
VpssDev Selection
| Input | VpssDev |
|---|---|
| Camera (ISP) | 1 |
| File/Memory | 0 |
VB Pool Sizing
Size = COMMON_GetPicBufferSize(w, h, fmt, DATA_BITWIDTH_8, COMPRESS_MODE_NONE, 0)
Counts: Camera=4-6, VPSS=3-4, Encode=2-3, Decode=4-6
Debug Commands
cat /proc/cvitek/sys | grep -A 10 "BIND RELATION"
cat /proc/cvitek/vb | grep -A 20 "PoolId"
cat /proc/cvitek/vi | grep -A 5 "VI CHN STATUS"
cat /proc/cvitek/vpss | grep -A 20 "WORK STATUS"
echo "VI=7" > /proc/cvitek/log
Version: 2.4.0 | Updated: 2026-01-20 | Platform: SG200X