Please provide complete information as applicable to your setup.
• Hardware Platform (Jetson / GPU) RTX4080
• DeepStream Version 6.4
Trying to extract image data from NvDsFrameMeta and encode to base64 char array so that I can send image data in mqtt.
I have the following code in deepstream_app.c.
The code is implemented in write_kitti_output.
The error is
deepstream_app.c:464:43: error: ‘NvDsFrameMeta’ {aka ‘struct _NvDsFrameMeta’} has no member named ‘input_buffer’
464 | GstBuffer *buffer = frame_meta->input_buffer;
How can I have buffer from frame_meta?
// Function to encode a byte array to base64
char *base64_encode(const unsigned char *src, size_t len) {
static const char base64chars[] =
"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
char *out, *pos;
const unsigned char *end, *in;
size_t olen;
olen = 4 * ((len + 2) / 3); // 3-byte blocks to 4-byte
if (olen < len) {
return NULL; // integer overflow
}
out = (char *)malloc(olen);
if (out == NULL) {
return NULL;
}
end = src + len;
in = src;
pos = out;
while (end - in >= 3) {
*pos++ = base64chars[in[0] >> 2];
*pos++ = base64chars[((in[0] & 0x03) << 4) | (in[1] >> 4)];
*pos++ = base64chars[((in[1] & 0x0f) << 2) | (in[2] >> 6)];
*pos++ = base64chars[in[2] & 0x3f];
in += 3;
}
if (end - in) {
*pos++ = base64chars[in[0] >> 2];
if (end - in == 1) {
*pos++ = base64chars[(in[0] & 0x03) << 4];
*pos++ = '=';
} else {
*pos++ = base64chars[((in[0] & 0x03) << 4) |
(in[1] >> 4)];
*pos++ = base64chars[(in[1] & 0x0f) << 2];
}
*pos++ = '=';
}
return out;
}
static void
write_kitti_output (AppCtx * appCtx, NvDsBatchMeta * batch_meta, NvBufSurface *ip_surf )
{
for (NvDsMetaList * l_frame = batch_meta->frame_meta_list; l_frame != NULL; l_frame = l_frame->next) {
NvDsFrameMeta *frame_meta = (NvDsFrameMeta *) l_frame->data;
guint stream_id = frame_meta->pad_index;
for (NvDsMetaList * l_obj = frame_meta->obj_meta_list; l_obj != NULL; l_obj = l_obj->next) {
NvDsObjectMeta *obj = (NvDsObjectMeta *) l_obj->data;
int left = (int)obj->rect_params.left;
int top = (int)obj->rect_params.top;
int right = (int)(left + obj->rect_params.width);
int bottom = (int)(top + obj->rect_params.height);
float confidence = obj->confidence;
//printf ("%s 0.0 0 0.0 %f %f %f %f 0.0 0.0 0.0 0.0 0.0 0.0 0.0 %f\n", obj->obj_label, left, top, right, bottom, confidence);
if(strcmp(obj->obj_label,"person")==0)
{
}
}
//Image data management
GstBuffer *buffer = frame_meta->input_buffer;
if (!buffer) {
continue;
}
guint buffer_size = gst_buffer_get_size(buffer);
g_print("Buffer size: %u\n", buffer_size);
//Map the buffer to CUDA memory
NvBufSurface *surface = NULL;
if (!gst_nvbuffer_surface_map (buffer, &surface)) {
g_printerr("Failed to map GstBuffer to NvBufSurface\n");
continue;
}
// Copy the CUDA memory to CPU-accessible memory
void *cpu_buffer = NULL;
size_t cpu_size = surface->surfaceList[0].dataSize;
cudaError_t cuda_err = cudaMallocHost(&cpu_buffer, cpu_size);
if (cuda_err != cudaSuccess) {
g_printerr("Failed to allocate CPU memory: %s\n", cudaGetErrorString(cuda_err));
gst_buffer_unmap(buffer, surface);
continue;
}
cudaMemcpy(cpu_buffer, surface->surfaceList[0].mappedAddr.addr[0], cpu_size, cudaMemcpyDeviceToHost);
// Now you have the image data in cpu_buffer
// You can perform further processing on it as needed
char *base64Image = base64_encode(cpu_buffer, strlen((char *)cpu_buffer));
if (base64Image == NULL) {
fprintf(stderr, "Failed to encode image data to base64\n");
return -1;
}
// Free the CUDA memory
cudaFreeHost(cpu_buffer);
// Unmap the buffer
gst_buffer_unmap(buffer, surface);
}
number_of_frames = 0;
}
}