Exception thrown at 0x7C2E6005 (swscale-5.dll) in Video_playing.exe: 0xC0000005: Access violation reading location 0xCCCCCD04

Trying to play a video using GLFW and FFmpeg on visual studio 2019 on windows 10.

Exception is thrown at sws_scale(sws_scaler_ctx, av_frame->data, av_frame->linesize, 0, av_frame->height, dest, dest_linesize); in the code. Don't know why this is occurred. Please Help!!

#include "video_reader.h"
#include <stdio.h>

bool video_reader_read_frame(VideoReaderState* state, uint8_t* frame_buffer, int64_t* pts) {

    // Unpack members of state
    auto& width = state->width;
    auto& height = state->height;
    auto& av_format_ctx = state->av_format_ctx;
    auto& av_codec_ctx = state->av_codec_ctx;
    auto& video_stream_index = state->video_stream_index;
    auto& av_frame = state->av_frame;
    auto& av_packet = state->av_packet;
    auto& sws_scaler_ctx = state->sws_scaler_ctx;

    // Decode one frame
    int response;
    while (av_read_frame(av_format_ctx, av_packet) >= 0) {
        if (av_packet->stream_index != video_stream_index) {
            av_packet_unref(av_packet);
            continue;
        }

        response = avcodec_send_packet(av_codec_ctx, av_packet);
        if (response < 0) {
            printf("Failed to decode packet: %s\n", response);
            return false;
        }

        response = avcodec_receive_frame(av_codec_ctx, av_frame);
        if (response == AVERROR(EAGAIN) || response == AVERROR_EOF) {
            av_packet_unref(av_packet);
            continue;
        }
        else if (response < 0) {
            printf("Failed to decode packet: %s\n", response);
            return false;
        }

        av_packet_unref(av_packet);
        break;
    }

    *pts = av_frame->pts;

    // Set up sws scaler
    if (!sws_scaler_ctx) {
        sws_scaler_ctx = sws_getContext(width, height, av_codec_ctx->pix_fmt,
            width, height, AV_PIX_FMT_RGB0,
            SWS_BILINEAR, NULL, NULL, NULL);
    }
    if (!sws_scaler_ctx) {
        printf("Couldn't initialize sw scaler\n");
        return false;
    }

    uint8_t* dest[4] = { frame_buffer, NULL, NULL, NULL };
    int dest_linesize[4] = { width * 4, 0, 0, 0 };
    sws_scale(sws_scaler_ctx, av_frame->data, av_frame->linesize, 0, av_frame->height, dest, dest_linesize);

    return true;
}