实现dump 函数

实现1

void dumpBufferToFile(buffer_handle_t* buffer, int width, int height, int frameNum) {void* data = NULL;GraphicBufferMapper::getInstance().lock(*buffer, GRALLOC_USAGE_SW_READ_OFTEN, Rect(width, height), &data);char filename[128];sprintf(filename, "/data/vendor/camera/frame_%04d.yuv", frameNum);FILE* fp = fopen(filename, "wb");if (fp && data) {fwrite(data, 1, width * height * 3 / 2, fp); // 如果是 NV12/YUV420fclose(fp);}GraphicBufferMapper::getInstance().unlock(*buffer);
}

实现2

#include <stdio.h>
#include <fcntl.h>
#include <string>
#include <sys/mman.h>
#include <hardware/gralloc.h>
#include <ui/GraphicBufferMapper.h>
#include <cutils/native_handle.h>
#include <android/hardware_buffer.h>using namespace android;// Camera format types
#define CAMERA_FORMAT_RAW16   0x20
#define CAMERA_FORMAT_RAW10   0x25
#define CAMERA_FORMAT_RAW12   0x26
#define CAMERA_FORMAT_YUV_420_888 0x23
#define CAMERA_FORMAT_JPEG    0x100// Helper: Get format name
const char* getFormatSuffix(int format) {switch (format) {case HAL_PIXEL_FORMAT_YCbCr_420_888:return ".yuv";case HAL_PIXEL_FORMAT_BLOB:return ".jpg";case HAL_PIXEL_FORMAT_RAW16:return ".raw16";case HAL_PIXEL_FORMAT_RAW10:return ".raw10";case HAL_PIXEL_FORMAT_RAW12:return ".raw12";default:return ".bin";}
}void dumpBufferToFile(buffer_handle_t handle, int width, int height, int frameNum, int format) {void* data = nullptr;uint32_t size = 0;// Lock buffer for readingGraphicBufferMapper& mapper = GraphicBufferMapper::get();android_ycbcr ycbcr = {};int usage = GRALLOC_USAGE_SW_READ_OFTEN;if (format == HAL_PIXEL_FORMAT_YCbCr_420_888) {if (mapper.lockYCbCr(handle, usage, {0, 0, width, height}, &ycbcr) == OK) {data = ycbcr.y;size = width * height * 3 / 2;}} else {if (mapper.lock(handle, usage, {0, 0, width, height}, &data) == OK) {switch (format) {case HAL_PIXEL_FORMAT_RAW16:size = width * height * 2;break;case HAL_PIXEL_FORMAT_RAW10:size = width * height * 10 / 8;break;case HAL_PIXEL_FORMAT_RAW12:size = width * height * 12 / 8;break;case HAL_PIXEL_FORMAT_BLOB:// BLOB: Usually JPEG// You may need to get actual size from metadata, here we assume maxsize = width * height;break;default:size = width * height * 4; // assume RGBA fallback}}}if (data == nullptr || size == 0) {ALOGE("dumpBufferToFile: failed to lock buffer");return;}// Generate file pathchar path[256];snprintf(path, sizeof(path), "/data/vendor/camera/dump_%04d%s", frameNum, getFormatSuffix(format));// Dump to fileFILE* fp = fopen(path, "wb");if (fp) {fwrite(data, 1, size, fp);fclose(fp);ALOGI("dumpBufferToFile: dumped frame %d to %s", frameNum, path);} else {ALOGE("dumpBufferToFile: failed to open file %s", path);}// Unlock buffermapper.unlock(handle);
}

添加调用位置

推荐位置 1， Camera3OutputStream::queueBufferToConsumer()

此函数负责将 HAL 返回的 buffer 通过 ANativeWindow 传给 Surface，因此非常适合 dump。

status_t Camera3OutputStream::queueBufferToConsumer(sp<GraphicBuffer>& buffer, ...)
{dumpBufferToFile(buffer->getNativeBuffer()->handle, mWidth, mHeight, mFrameNumber);// 原逻辑继续res = mConsumer->queueBuffer(...);
}

推荐位置 2，Camera3Device::processCaptureResult()

HAL 返回一个 camera3_capture_result_t 结构，这里可以拿到 metadata 和 buffer。

    for (size_t i = 0; i < result->num_output_buffers; i++) {const camera3_stream_buffer_t &buffer = result->output_buffers[i];Camera3OutputStreamInterface* stream = static_cast<Camera3OutputStreamInterface*>(buffer.stream->priv);// 📌 拿到 buffer 后 dumpdumpBufferToFile(buffer.buffer, stream->getWidth(), stream->getHeight(), result->frame_number);}
}