openmv/src/omv/framebuffer.c
Kwabena W. Agyeman 98e1a1e51d Add disable_fb.
Allow user control to disable the frame buffer.

Necessary for high speed frame streaming.
2020-04-30 13:40:07 -07:00

158 lines
5.6 KiB
C

/*
* This file is part of the OpenMV project.
*
* Copyright (c) 2013-2019 Ibrahim Abdelkader <iabdalkader@openmv.io>
* Copyright (c) 2013-2019 Kwabena W. Agyeman <kwagyeman@openmv.io>
*
* This work is licensed under the MIT license, see the file LICENSE for details.
*
* Framebuffer functions.
*/
#include "mpprint.h"
#include "framebuffer.h"
#include "omv_boardconfig.h"
extern char _fb_base;
framebuffer_t *fb_framebuffer = (framebuffer_t *) &_fb_base;
extern char _jpeg_buf;
jpegbuffer_t *jpeg_fb_framebuffer = (jpegbuffer_t *) &_jpeg_buf;
void set_fb_streaming_disabled(bool en)
{
MAIN_FB()->fb_streaming_disable = en;
}
bool is_fb_streaming_disabled()
{
return MAIN_FB()->fb_streaming_disable;
}
int encode_for_ide_new_size(image_t *img)
{
return (((img->bpp * 8) + 5) / 6) + 2;
}
void encode_for_ide(uint8_t *ptr, image_t *img)
{
*ptr++ = 0xFE;
for(int i = 0, j = (img->bpp / 3) * 3; i < j; i += 3) {
int x = 0;
x |= img->data[i + 0] << 0;
x |= img->data[i + 1] << 8;
x |= img->data[i + 2] << 16;
*ptr++ = 0x80 | ((x >> 0) & 0x3F);
*ptr++ = 0x80 | ((x >> 6) & 0x3F);
*ptr++ = 0x80 | ((x >> 12) & 0x3F);
*ptr++ = 0x80 | ((x >> 18) & 0x3F);
}
if((img->bpp % 3) == 2) { // 2 bytes -> 16-bits -> 24-bits sent
int x = 0;
x |= img->data[img->bpp - 2] << 0;
x |= img->data[img->bpp - 1] << 8;
*ptr++ = 0x80 | ((x >> 0) & 0x3F);
*ptr++ = 0x80 | ((x >> 6) & 0x3F);
*ptr++ = 0x80 | ((x >> 12) & 0x3F);
}
if((img->bpp % 3) == 1) { // 1 byte -> 8-bits -> 16-bits sent
int x = 0;
x |= img->data[img->bpp - 1] << 0;
*ptr++ = 0x80 | ((x >> 0) & 0x3F);
*ptr++ = 0x80 | ((x >> 6) & 0x3F);
}
*ptr++ = 0xFE;
}
uint32_t fb_buffer_size()
{
switch (MAIN_FB()->bpp) {
case IMAGE_BPP_BINARY: {
return ((MAIN_FB()->w + UINT32_T_MASK) >> UINT32_T_SHIFT) * MAIN_FB()->h;
}
case IMAGE_BPP_GRAYSCALE: {
return (MAIN_FB()->w * MAIN_FB()->h) * sizeof(uint8_t);
}
case IMAGE_BPP_RGB565: {
return (MAIN_FB()->w * MAIN_FB()->h) * sizeof(uint16_t);
}
case IMAGE_BPP_BAYER: {
return MAIN_FB()->w * MAIN_FB()->h;
}
default: { // JPEG
return MAIN_FB()->bpp;
}
}
}
void fb_update_jpeg_buffer()
{
static int overflow_count = 0;
if ((!MAIN_FB()->fb_streaming_disable) && JPEG_FB()->enabled) {
if (MAIN_FB()->bpp > 3) {
bool does_not_fit = false;
// Lock FB
if (mutex_try_lock(&JPEG_FB()->lock, MUTEX_TID_OMV)) {
if((OMV_JPEG_BUF_SIZE-64) < MAIN_FB()->bpp) {
// image won't fit. so don't copy.
JPEG_FB()->w = 0; JPEG_FB()->h = 0; JPEG_FB()->size = 0;
does_not_fit = true;
} else {
memcpy(JPEG_FB()->pixels, MAIN_FB()->pixels, MAIN_FB()->bpp);
JPEG_FB()->w = MAIN_FB()->w; JPEG_FB()->h = MAIN_FB()->h; JPEG_FB()->size = MAIN_FB()->bpp;
}
// Unlock the framebuffer mutex
mutex_unlock(&JPEG_FB()->lock, MUTEX_TID_OMV);
}
if (does_not_fit) {
image_t out = { .w=MAIN_FB()->w, .h=MAIN_FB()->h, .bpp=MAIN_FB()->bpp, .data=MAIN_FB()->pixels };
int new_size = encode_for_ide_new_size(&out);
fb_alloc_mark();
uint8_t *temp = fb_alloc(new_size, FB_ALLOC_NO_HINT);
encode_for_ide(temp, &out);
(MP_PYTHON_PRINTER)->print_strn((MP_PYTHON_PRINTER)->data, (const char *) temp, new_size);
fb_alloc_free_till_mark();
}
} else if (MAIN_FB()->bpp >= 0) {
// Lock FB
if (mutex_try_lock(&JPEG_FB()->lock, MUTEX_TID_OMV)) {
// Set JPEG src and dst images.
image_t src = {.w=MAIN_FB()->w, .h=MAIN_FB()->h, .bpp=MAIN_FB()->bpp, .pixels=MAIN_FB()->pixels};
image_t dst = {.w=MAIN_FB()->w, .h=MAIN_FB()->h, .bpp=(OMV_JPEG_BUF_SIZE-64), .pixels=JPEG_FB()->pixels};
// Note: lower quality saves USB bandwidth and results in a faster IDE FPS.
bool overflow = jpeg_compress(&src, &dst, JPEG_FB()->quality, false);
if (overflow == true) {
// JPEG buffer overflowed, reduce JPEG quality for the next frame
// and skip the current frame. The IDE doesn't receive this frame.
if (JPEG_FB()->quality > 1) {
// Keep this quality for the next n frames
overflow_count = 60;
JPEG_FB()->quality = IM_MAX(1, (JPEG_FB()->quality/2));
}
JPEG_FB()->w = 0; JPEG_FB()->h = 0; JPEG_FB()->size = 0;
} else {
if (overflow_count) {
overflow_count--;
}
// No buffer overflow, increase quality up to max quality based on frame size
if (overflow_count == 0 && JPEG_FB()->quality
< ((fb_buffer_size() > JPEG_QUALITY_THRESH) ? JPEG_QUALITY_LOW:JPEG_QUALITY_HIGH)) {
JPEG_FB()->quality++;
}
// Set FB from JPEG image
JPEG_FB()->w = dst.w; JPEG_FB()->h = dst.h; JPEG_FB()->size = dst.bpp;
}
// Unlock the framebuffer mutex
mutex_unlock(&JPEG_FB()->lock, MUTEX_TID_OMV);
}
}
}
}