FFMPEG and STB_Image Create awful Picture - c

Question

I was learning how to use the FFMPEG C api and I was trying to encode a jpeg into a MPEG file. I load the JPEG into (unsigned char *) using the stb-image library. Then I create a (uint8_t *) and copy my rgb values. Finally, I convert RGB to YUV420 using sws_scale. However, a portion of my image blurs out when I perform the encoding.
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This is the original image
Perhaps I allocate my frame buffer incorrectly?
ret = av_frame_get_buffer(frame, 0);
This is my entire program
#define STB_IMAGE_IMPLEMENTATION
#include "stb_image.h"
#define STB_IMAGE_WRITE_IMPLEMENTATION
#include "stb_image_write.h"
#define STB_IMAGE_RESIZE_IMPLEMENTATION
#include "stb_image_resize.h"
#include <assert.h>
#include <libavcodec/avcodec.h>
#include <libavutil/opt.h>
#include <libavutil/imgutils.h>
#include <libswscale/swscale.h>
//gcc stack.c -lm -o stack.o `pkg-config --cflags --libs libavformat libavcodec libswresample libswscale libavutil` && ./stack.o
/*
int i : pts of current frame
*/
void PictureToFrame(int i, AVFrame *frame, int height, int width)
{
//Use stb image to get rgb values
char *fileName = "profil.jpeg";
int imageHeight = 0;
int imageWidth = 0;
int colorChannels = 0;
int arrayLength = 0;
unsigned char *image = stbi_load(fileName,&imageWidth,&imageHeight,&colorChannels,0);
printf("(height: %d, width: %d)\n",imageHeight, imageWidth);
assert(colorChannels == 3 && imageHeight == height && imageWidth == width);
//Convert unsigned char * to uint8_t *
arrayLength = imageHeight * imageWidth * colorChannels;
uint8_t *rgb = calloc(arrayLength, sizeof(uint8_t));
int j = arrayLength-1;
for(int i = 0; i < arrayLength; i++)
{
rgb[i] = (uint8_t) image[i];
}
//Use SwsContext to scale RGB to YUV420P and write to frame
const int in_linesize[1] = { 3* imageWidth};
struct SwsContext *sws_context = NULL;
sws_context = sws_getCachedContext(sws_context,
imageWidth, imageHeight, AV_PIX_FMT_RGB24,
imageWidth, imageHeight, AV_PIX_FMT_YUV420P,
0, 0, 0, 0);
sws_scale(sws_context, (const uint8_t * const *)&rgb, in_linesize, 0,
imageHeight, frame->data, frame->linesize);
//Save frame pts
frame->pts = i;
//Free alloc'd data
stbi_image_free(image);
sws_freeContext(sws_context);
free(rgb);
}
static void encode(AVCodecContext *enc_ctx, AVFrame *frame, AVPacket *pkt, FILE *outfile)
{
int returnValue;
/* send the frame to the encoder */
if(frame)
{
printf("Send frame %3"PRId64"\n", frame->pts);
}
returnValue = avcodec_send_frame(enc_ctx, frame);
if(returnValue < 0)
{
printf("Error sending a frame for encoding\n");
return;
}
while(returnValue >= 0)
{
returnValue = avcodec_receive_packet(enc_ctx, pkt);
if(returnValue == AVERROR(EAGAIN) || returnValue == AVERROR_EOF)
{
return;
}
else if(returnValue < 0)
{
printf("Error during encoding\n");
return;
}
printf("Write packet %3"PRId64" (size=%5d)\n", pkt->pts, pkt->size);
fwrite(pkt->data, 1, pkt->size, outfile);
av_packet_unref(pkt);
}
}
int main(int argc, char **argv)
{
const char *filename, *codec_name;
const AVCodec *codec;
AVCodecContext *c= NULL;
int i, ret, x, y;
FILE *f;
AVFrame *frame;
AVPacket *pkt;
uint8_t endcode[] = { 0, 0, 1, 0xb7 };
filename = "outo.mp4";
codec_name = "mpeg1video";//"mpeg1video";//"libx264";
/* find the mpeg1video encoder */
codec = avcodec_find_encoder_by_name(codec_name);
if(!codec)
{
printf("Error finding codec\n");
return 0;
}
c = avcodec_alloc_context3(codec);
if(!c)
{
printf("Error allocating c\n");
return 0;
}
pkt = av_packet_alloc();
if(!pkt)
{
printf("Error allocating pkt\n");
return 0;
}
/* put sample parameters */
c->bit_rate = 400000;
/* resolution must be a multiple of two */
c->width = 800;
c->height = 800;
/* frames per second */
c->time_base = (AVRational){1, 25};
c->framerate = (AVRational){25, 1};
c->gop_size = 10;
c->max_b_frames = 1;
c->pix_fmt = AV_PIX_FMT_YUV420P;
if(codec->id == AV_CODEC_ID_H264)
{
av_opt_set(c->priv_data, "preset", "slow", 0);
}
/* open it */
ret = avcodec_open2(c, codec, NULL);
if(ret < 0)
{
printf("Error opening codec\n");
return 0;
}
f = fopen(filename, "wb");
if(!f)
{
printf("Error opening file\n");
return 0;
}
frame = av_frame_alloc();
if(!frame)
{
printf("Error allocating frame\n");
return 0;
}
frame->format = c->pix_fmt;
frame->width = c->width;
frame->height = c->height;
//I suspect this is the problem
ret = av_frame_get_buffer(frame, 0);
if(ret < 0)
{
fprintf(stderr, "Could not allocate the video frame data\n");
exit(1);
}
/* encode 25 frames*/
for(i = 0; i < 25; i++)
{
/* make sure the frame data is writable */
ret = av_frame_make_writable(frame);
if(ret < 0)
{
return 0;
}
//FIll Frame with picture data
PictureToFrame(i, frame, c->height, c->width);
/* encode the image */
encode(c, frame, pkt, f);
}
/* flush the encoder */
encode(c, NULL, pkt, f);
/* add sequence end code to have a real MPEG file */
if (codec->id == AV_CODEC_ID_MPEG1VIDEO || codec->id == AV_CODEC_ID_MPEG2VIDEO)
fwrite(endcode, 1, sizeof(endcode), f);
fclose(f);
avcodec_free_context(&c);
av_frame_free(&frame);
av_packet_free(&pkt);
return 0;
}