AI-on-the-edge-device/code/lib/conversions/to_jpg.cpp

// Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include <stddef.h>
#include <string.h>
#include "esp_attr.h"
#include "soc/efuse_reg.h"
#include "esp_heap_caps.h"
#include <esp_camera.h>
#include "img_converters.h"
#include "jpge.h"
#include "yuv.h"

#include "esp_system.h"
#if ESP_IDF_VERSION_MAJOR >= 4 // IDF 4+
#if CONFIG_IDF_TARGET_ESP32 // ESP32/PICO-D4
#include "esp32/spiram.h"
#else 
#error Target CONFIG_IDF_TARGET is not supported
#endif
#else // ESP32 Before IDF 4.0
#include "esp_spiram.h"
#endif

#if defined(ARDUINO_ARCH_ESP32) && defined(CONFIG_ARDUHAL_ESP_LOG)
#include "esp32-hal-log.h"
#define TAG ""
#else
#include "esp_log.h"
static const char* TAG = "to_jpg";
#endif

static void *_malloc(size_t size)
{
    void * res = malloc(size);
    if(res) {
        return res;
    }
    return heap_caps_malloc(size, MALLOC_CAP_SPIRAM | MALLOC_CAP_8BIT);
}

static IRAM_ATTR void convert_line_format(uint8_t * src, pixformat_t format, uint8_t * dst, size_t width, size_t in_channels, size_t line)
{
    int i=0, o=0, l=0;
    if(format == PIXFORMAT_GRAYSCALE) {
        memcpy(dst, src + line * width, width);
    } else if(format == PIXFORMAT_RGB888) {
        l = width * 3;
        src += l * line;
        for(i=0; i<l; i+=3) {
            dst[o++] = src[i+2];
            dst[o++] = src[i+1];
            dst[o++] = src[i];
        }
    } else if(format == PIXFORMAT_RGB565) {
        l = width * 2;
        src += l * line;
        for(i=0; i<l; i+=2) {
            dst[o++] = src[i] & 0xF8;
            dst[o++] = (src[i] & 0x07) << 5 | (src[i+1] & 0xE0) >> 3;
            dst[o++] = (src[i+1] & 0x1F) << 3;
        }
    } else if(format == PIXFORMAT_YUV422) {
        uint8_t y0, y1, u, v;
        uint8_t r, g, b;
        l = width * 2;
        src += l * line;
        for(i=0; i<l; i+=4) {
            y0 = src[i];
            u = src[i+1];
            y1 = src[i+2];
            v = src[i+3];

            yuv2rgb(y0, u, v, &r, &g, &b);
            dst[o++] = r;
            dst[o++] = g;
            dst[o++] = b;

            yuv2rgb(y1, u, v, &r, &g, &b);
            dst[o++] = r;
            dst[o++] = g;
            dst[o++] = b;
        }
    }
}

bool convert_image(uint8_t *src, uint16_t width, uint16_t height, pixformat_t format, uint8_t quality, jpge::output_stream *dst_stream)
{
    int num_channels = 3;
    jpge::subsampling_t subsampling = jpge::H2V2;

    if(format == PIXFORMAT_GRAYSCALE) {
        num_channels = 1;
        subsampling = jpge::Y_ONLY;
    }

    if(!quality) {
        quality = 1;
    } else if(quality > 100) {
        quality = 100;
    }

    jpge::params comp_params = jpge::params();
    comp_params.m_subsampling = subsampling;
    comp_params.m_quality = quality;

    jpge::jpeg_encoder dst_image;

    if (!dst_image.init(dst_stream, width, height, num_channels, comp_params)) {
        ESP_LOGE(TAG, "JPG encoder init failed");
        return false;
    }

    uint8_t* line = (uint8_t*)_malloc(width * num_channels);
    if(!line) {
        ESP_LOGE(TAG, "Scan line malloc failed");
        return false;
    }

    for (int i = 0; i < height; i++) {
        convert_line_format(src, format, line, width, num_channels, i);
        if (!dst_image.process_scanline(line)) {
            ESP_LOGE(TAG, "JPG process line %u failed", i);
            free(line);
            return false;
        }
    }
    free(line);

    if (!dst_image.process_scanline(NULL)) {
        ESP_LOGE(TAG, "JPG image finish failed");
        return false;
    }
    dst_image.deinit();
    return true;
}

class callback_stream : public jpge::output_stream {
protected:
    jpg_out_cb ocb;
    void * oarg;
    size_t index;

public:
    callback_stream(jpg_out_cb cb, void * arg) : ocb(cb), oarg(arg), index(0) { }
    virtual ~callback_stream() { }
    virtual bool put_buf(const void* data, int len)
    {
        index += ocb(oarg, index, data, len);
        return true;
    }
    virtual size_t get_size() const
    {
        return index;
    }
};

bool fmt2jpg_cb(uint8_t *src, size_t src_len, uint16_t width, uint16_t height, pixformat_t format, uint8_t quality, jpg_out_cb cb, void * arg)
{
    callback_stream dst_stream(cb, arg);
    return convert_image(src, width, height, format, quality, &dst_stream);
}

bool frame2jpg_cb(camera_fb_t * fb, uint8_t quality, jpg_out_cb cb, void * arg)
{
    return fmt2jpg_cb(fb->buf, fb->len, fb->width, fb->height, fb->format, quality, cb, arg);
}



class memory_stream : public jpge::output_stream {
protected:
    uint8_t *out_buf;
    size_t max_len, index;

public:
    memory_stream(void *pBuf, uint buf_size) : out_buf(static_cast<uint8_t*>(pBuf)), max_len(buf_size), index(0) { }

    virtual ~memory_stream() { }

    virtual bool put_buf(const void* pBuf, int len)
    {
        if (!pBuf) {
            //end of image
            return true;
        }
        if ((size_t)len > (max_len - index)) {
            ESP_LOGW(TAG, "JPG output overflow: %d bytes", len - (max_len - index));
            len = max_len - index;
        }
        if (len) {
            memcpy(out_buf + index, pBuf, len);
            index += len;
        }
        return true;
    }

    virtual size_t get_size() const
    {
        return index;
    }
};

bool fmt2jpg(uint8_t *src, size_t src_len, uint16_t width, uint16_t height, pixformat_t format, uint8_t quality, uint8_t ** out, size_t * out_len)
{
    //todo: allocate proper buffer for holding JPEG data
    //this should be enough for CIF frame size
//    int jpg_buf_len = 64*1024;
    int jpg_buf_len = 256*1024;     // Anpassung wg. zu kleiner Bitmaps


    uint8_t * jpg_buf = (uint8_t *)_malloc(jpg_buf_len);
    if(jpg_buf == NULL) {
        ESP_LOGE(TAG, "JPG buffer malloc failed");
        return false;
    }
    memory_stream dst_stream(jpg_buf, jpg_buf_len);

    if(!convert_image(src, width, height, format, quality, &dst_stream)) {
        free(jpg_buf);
        return false;
    }

    *out = jpg_buf;
    *out_len = dst_stream.get_size();
    return true;
}

bool frame2jpg(camera_fb_t * fb, uint8_t quality, uint8_t ** out, size_t * out_len)
{
    return fmt2jpg(fb->buf, fb->len, fb->width, fb->height, fb->format, quality, out, out_len);
}