How to resize a picture using ffmpeg's sws_scale()? - ffmpeg

I wanna resize a picture by using the ffmpeg's func--->sws_scale().
Is there any one knows how to do it?
Do you have the source code for this function?

First you need to create a SwsContext (you need to do this only once) :
struct SwsContext *resize;
resize = sws_getContext(width1, height1, AV_PIX_FMT_YUV420P, width2, height2, PIX_FMT_RGB24, SWS_BICUBIC, NULL, NULL, NULL);
You need two frames for conversion, frame1 is the original frame, you need to explicitly allocate frame2 :
AVFrame* frame1 = avcodec_alloc_frame(); // this is your original frame
AVFrame* frame2 = avcodec_alloc_frame();
int num_bytes = avpicture_get_size(AV_PIX_FMT_RGB24, width2, height2);
uint8_t* frame2_buffer = (uint8_t *)av_malloc(num_bytes*sizeof(uint8_t));
avpicture_fill((AVPicture*)frame2, frame2_buffer, AV_PIX_FMT_RGB24, width2, height2);
You may use this part inside a loop if you need to resize each frame you receive :
// frame1 should be filled by now (eg using avcodec_decode_video)
sws_scale(resize, frame1->data, frame1->linesize, 0, height1, frame2->data, frame2->linesize);
Note that I also changed pixel format, but you can use the same pixel format for both frames

Runnable example in FFmpeg 2.8
Basically using arash's method, but runnable so you can try it out.
Generate one short video procedurally, and then convert it to 3 different sizes.
ffmpeg_encoder_init_frame and ffmpeg_encoder_scale are the key methods.
Source:
#include <libavcodec/avcodec.h>
#include <libavutil/imgutils.h>
#include <libavutil/opt.h>
#include <libswscale/swscale.h>
static AVCodecContext *c = NULL;
static AVFrame *frame;
static AVFrame *frame2;
static AVPacket pkt;
static FILE *file;
static struct SwsContext *sws_context = NULL;
static void ffmpeg_encoder_init_frame(AVFrame **framep, int width, int height) {
int ret;
AVFrame *frame;
frame = av_frame_alloc();
if (!frame) {
fprintf(stderr, "Could not allocate video frame\n");
exit(1);
}
frame->format = c->pix_fmt;
frame->width = width;
frame->height = height;
ret = av_image_alloc(frame->data, frame->linesize, frame->width, frame->height, frame->format, 32);
if (ret < 0) {
fprintf(stderr, "Could not allocate raw picture buffer\n");
exit(1);
}
*framep = frame;
}
static void ffmpeg_encoder_scale(uint8_t *rgb) {
sws_context = sws_getCachedContext(sws_context,
frame->width, frame->height, AV_PIX_FMT_YUV420P,
frame2->width, frame2->height, AV_PIX_FMT_YUV420P,
SWS_BICUBIC, NULL, NULL, NULL);
sws_scale(sws_context, (const uint8_t * const *)frame->data, frame->linesize, 0,
frame->height, frame2->data, frame2->linesize);
}
static void ffmpeg_encoder_set_frame_yuv_from_rgb(uint8_t *rgb) {
const int in_linesize[1] = { 3 * frame->width };
sws_context = sws_getCachedContext(sws_context,
frame->width, frame->height, AV_PIX_FMT_RGB24,
frame->width, frame->height, AV_PIX_FMT_YUV420P,
0, NULL, NULL, NULL);
sws_scale(sws_context, (const uint8_t * const *)&rgb, in_linesize, 0,
frame->height, frame->data, frame->linesize);
}
void generate_rgb(int width, int height, int pts, uint8_t **rgbp) {
int x, y, cur;
uint8_t *rgb = *rgbp;
rgb = realloc(rgb, 3 * sizeof(uint8_t) * height * width);
for (y = 0; y < height; y++) {
for (x = 0; x < width; x++) {
cur = 3 * (y * width + x);
rgb[cur + 0] = 0;
rgb[cur + 1] = 0;
rgb[cur + 2] = 0;
if ((frame->pts / 25) % 2 == 0) {
if (y < height / 2) {
if (x < width / 2) {
/* Black. */
} else {
rgb[cur + 0] = 255;
}
} else {
if (x < width / 2) {
rgb[cur + 1] = 255;
} else {
rgb[cur + 2] = 255;
}
}
} else {
if (y < height / 2) {
rgb[cur + 0] = 255;
if (x < width / 2) {
rgb[cur + 1] = 255;
} else {
rgb[cur + 2] = 255;
}
} else {
if (x < width / 2) {
rgb[cur + 1] = 255;
rgb[cur + 2] = 255;
} else {
rgb[cur + 0] = 255;
rgb[cur + 1] = 255;
rgb[cur + 2] = 255;
}
}
}
}
}
*rgbp = rgb;
}
void ffmpeg_encoder_start(const char *filename, int codec_id, int fps, int width, int height, float factor) {
AVCodec *codec;
int ret;
int width2 = width * factor;
int height2 = height * factor;
avcodec_register_all();
codec = avcodec_find_encoder(codec_id);
if (!codec) {
fprintf(stderr, "Codec not found\n");
exit(1);
}
c = avcodec_alloc_context3(codec);
if (!c) {
fprintf(stderr, "Could not allocate video codec context\n");
exit(1);
}
c->bit_rate = 400000;
c->width = width2;
c->height = height2;
c->time_base.num = 1;
c->time_base.den = fps;
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);
if (avcodec_open2(c, codec, NULL) < 0) {
fprintf(stderr, "Could not open codec\n");
exit(1);
}
file = fopen(filename, "wb");
if (!file) {
fprintf(stderr, "Could not open %s\n", filename);
exit(1);
}
ffmpeg_encoder_init_frame(&frame, width, height);
ffmpeg_encoder_init_frame(&frame2, width2, height2);
}
void ffmpeg_encoder_finish(void) {
uint8_t endcode[] = { 0, 0, 1, 0xb7 };
int got_output, ret;
do {
fflush(stdout);
ret = avcodec_encode_video2(c, &pkt, NULL, &got_output);
if (ret < 0) {
fprintf(stderr, "Error encoding frame\n");
exit(1);
}
if (got_output) {
fwrite(pkt.data, 1, pkt.size, file);
av_packet_unref(&pkt);
}
} while (got_output);
fwrite(endcode, 1, sizeof(endcode), file);
fclose(file);
avcodec_close(c);
av_free(c);
av_freep(&frame->data[0]);
av_frame_free(&frame);
av_freep(&frame2->data[0]);
av_frame_free(&frame2);
}
void ffmpeg_encoder_encode_frame(uint8_t *rgb) {
int ret, got_output;
ffmpeg_encoder_set_frame_yuv_from_rgb(rgb);
ffmpeg_encoder_scale(rgb);
frame2->pts = frame->pts;
av_init_packet(&pkt);
pkt.data = NULL;
pkt.size = 0;
ret = avcodec_encode_video2(c, &pkt, frame2, &got_output);
if (ret < 0) {
fprintf(stderr, "Error encoding frame\n");
exit(1);
}
if (got_output) {
fwrite(pkt.data, 1, pkt.size, file);
av_packet_unref(&pkt);
}
}
static void encode_example(float factor) {
char filename[255];
int pts;
int width = 320;
int height = 240;
uint8_t *rgb = NULL;
snprintf(filename, 255, "tmp." __FILE__ ".%.2f.h264", factor);
ffmpeg_encoder_start(filename, AV_CODEC_ID_H264, 25, width, height, factor);
for (pts = 0; pts < 100; pts++) {
frame->pts = pts;
generate_rgb(width, height, pts, &rgb);
ffmpeg_encoder_encode_frame(rgb);
}
ffmpeg_encoder_finish();
free(rgb);
}
int main(void) {
encode_example(0.5);
encode_example(1.0);
encode_example(2.0);
return EXIT_SUCCESS;
}
Run with:
gcc main.c -lavformat -lavcodec -lswresample -lswscale -lavutil -lx264
./a.out
ffplay tmp.main.c.0.50.h264
ffplay tmp.main.c.1.00.h264
ffplay tmp.main.c.2.00.h264
Tested on ffmpeg 3.4.11, Ubuntu 16.04. Source on GitHub. Adapted from doc/examples/decoding_encoding.c.

Related

What is wrong while providing arguments for sws_scale?

In the following code, I can't figure out what's wrong:
uint8_t *dstData[4];
int dstLinesize[4];
AVPixelFormat convertToPixFmt = AV_PIX_FMT_RGBA;
int ret;
// ...
printf("tmp_frame format: %d (%s) %dx%d\n", tmp_frame->format, av_get_pix_fmt_name((AVPixelFormat)tmp_frame->format), tmp_frame->width, tmp_frame->height);
// The above line prints: tmp_frame format: 23 (nv12) 480x480
int size = av_image_get_buffer_size(convertToPixFmt, tmp_frame->width, tmp_frame->height, 1);
uint8_t *buffer = (uint8_t *) av_malloc(size);
ret = av_image_copy_to_buffer(buffer, size,
(const uint8_t * const *)&tmp_frame->data[i],
(const int *)&tmp_frame->linesize[i], (AVPixelFormat)tmp_frame->format,
tmp_frame->width, tmp_frame->height, 1);
ASSERT(ret >= 0);
ret = av_image_fill_arrays(dstData, dstLinesize, buffer, convertToPixFmt, dest_width, dest_height, 1);
ASSERT(ret >= 0);
ret = sws_scale(
convertContext,
dstData,
dstLinesize,
0,
dest_width,
convertedFrame->data,
convertedFrame->linesize);
printf("sws_scale returns %d\n", ret); // prints: sws_scale returns 0
ASSERT(ret == tmp_frame->height);
// ...
It's part of a code which uses dxva2 to obtain tmp_frame. I inspired the code from hw_decode.c and am sure that there's no mistake in the code. The tmp_frame is properly made in NV12 format. The error occurs just when I call sws_scale and it's:
bad src image pointers
So I don't know how to provide pointers not to get this error and sws_scale may work properly.
Any idea?
I update the question to include my whole code:
static AVBufferRef *hw_device_ctx = NULL;
static enum AVPixelFormat hw_pix_fmt;
static FILE *output_file = NULL;
int main(int argc, char *argv[])
{
AVFormatContext *input_ctx = NULL;
int video_stream, ret;
AVStream *video = NULL;
AVCodecContext *decoder_ctx = NULL;
AVCodec *decoder = NULL;
AVPacket packet;
enum AVHWDeviceType type;
int i;
if (argc < 2)
{
fprintf(stderr, "Usage: %s <input file>\n", argv[0]);
return -1;
}
type = av_hwdevice_find_type_by_name("dxva2");
ASSERT(type != AV_HWDEVICE_TYPE_NONE);
ASSERT(avformat_open_input(&input_ctx, argv[1], NULL, NULL) == 0);
ASSERT(avformat_find_stream_info(input_ctx, NULL) >= 0);
video_stream = av_find_best_stream(input_ctx, AVMEDIA_TYPE_VIDEO, -1, -1, &decoder, 0);
ASSERT(video_stream >= 0);
decoder_ctx = avcodec_alloc_context3(decoder);
ASSERT(decoder_ctx);
video = input_ctx->streams[video_stream];
ASSERT(avcodec_parameters_to_context(decoder_ctx, video->codecpar) >= 0);
ASSERT(av_hwdevice_ctx_create(&hw_device_ctx, type, NULL, NULL, 0) >= 0);
decoder_ctx->hw_device_ctx = av_buffer_ref(hw_device_ctx);
ASSERT(avcodec_open2(decoder_ctx, decoder, NULL) >= 0);
printf("video info: %dx%d\n", decoder_ctx->width, decoder_ctx->height);
AVFrame *frame = av_frame_alloc();
ASSERT(frame);
AVFrame *sw_frame = av_frame_alloc();
ASSERT(sw_frame);
AVFrame* convertedFrame = av_frame_alloc();
ASSERT(convertedFrame);
AVPixelFormat convertToPixFmt = AV_PIX_FMT_RGBA;
//int dest_width = 320, dest_height = 200;
int dest_width = decoder_ctx->width, dest_height = decoder_ctx->height;
SwsContext* convertContext = sws_getContext(decoder_ctx->width, decoder_ctx->height, AV_PIX_FMT_YUV420P,
dest_width, dest_height, convertToPixFmt,
SWS_FAST_BILINEAR, NULL, NULL, NULL);
ASSERT(convertContext);
int convertedFrameAspectBufferSize = avpicture_get_size(convertToPixFmt, dest_width, dest_height);
void *convertedFrameBuffer = av_malloc(convertedFrameAspectBufferSize);
avpicture_fill((AVPicture*)convertedFrame, (uint8_t *)convertedFrameBuffer, convertToPixFmt, dest_width, dest_height);
output_file = fopen("1.out", "w+");
for (int i = 0; /*i < 20*/; i++)
{
ret = av_read_frame(input_ctx, &packet);
if (ret == AVERROR_EOF)
break;
ASSERT(ret >= 0);
if (video_stream != packet.stream_index)
continue;
int ret = avcodec_send_packet(decoder_ctx, &packet);
ASSERT(ret >= 0);
//printf("%p", decoder->hw_configs->hwaccel);
ret = avcodec_receive_frame(decoder_ctx, frame);
if (ret < 0)
printf("%d\t%d\n", i, ret);
AVFrame *tmp_frame;
if (frame->format > 0) // hw enabled
{
ASSERT(av_hwframe_transfer_data(sw_frame, frame, 0) >= 0);
tmp_frame = sw_frame;
}
else
{
tmp_frame = frame;
}
printf("frame format: %d (%s) %dx%d\n", frame->format, av_get_pix_fmt_name((AVPixelFormat)frame->format), frame->width, frame->height);
printf("sw_frame format: %d (%s) %dx%d\n", sw_frame->format, av_get_pix_fmt_name((AVPixelFormat)sw_frame->format), sw_frame->width, sw_frame->height);
printf("tmp_frame format: %d (%s) %dx%d\n", tmp_frame->format, av_get_pix_fmt_name((AVPixelFormat)tmp_frame->format), tmp_frame->width, tmp_frame->height);
/*
video info: 480x480
frame format: 53 (dxva2_vld) 480x480
sw_frame format: 23 (nv12) 480x480
[swscaler # 004cb2c0] bad src image pointers
*/
int size = av_image_get_buffer_size(convertToPixFmt, tmp_frame->width, tmp_frame->height, 1);
uint8_t *buffer = (uint8_t *) av_malloc(size);
ret = av_image_copy_to_buffer(buffer, size,
(const uint8_t * const *)&tmp_frame->data[i],
(const int *)&tmp_frame->linesize[i], (AVPixelFormat)tmp_frame->format,
tmp_frame->width, tmp_frame->height, 1);
ASSERT(ret > 0);
ret = av_image_fill_arrays(dstData, dstLinesize, buffer, convertToPixFmt, dest_width, dest_height, 1);
ASSERT(ret > 0);
ret = sws_scale(
convertContext,
tmp_frame->data,
tmp_frame->linesize,
0,
dest_width,
convertedFrame->data,
convertedFrame->linesize);
printf("sws_scale returns %d\n", ret);
ASSERT(ret == tmp_frame->height);
ret = fwrite(convertedFrame->data, tmp_frame->height * tmp_frame->width, 1, output_file);
ASSERT(ret == 1);
break;
}
av_frame_free(&frame);
av_packet_unref(&packet);
avcodec_free_context(&decoder_ctx);
avformat_close_input(&input_ctx);
av_buffer_unref(&hw_device_ctx);
return 0;
}

FFMPEG RGB to YUV420P : Warning: data is not aligned! This can lead to a speedloss [duplicate]

This question already has answers here:
Pixel format conversion issue [FFMPEG]
(2 answers)
Closed 4 years ago.
I am trying to convert a standard RGB color space to YUV420P. I am struggling to figure out why I keep getting 'Warning: data is not aligned! This can lead to a speedloss' when executing the code. I have looked at a multitude of examples.
int ImageDecoder::rgb2yuv(uint8_t *src,
uint8_t *dest,
uint32_t width,
uint32_t height)
{
struct SwsContext *imgCtx = NULL;
AVFrame *pFrameYUV;
enum AVPixelFormat src_pix_fmt = AV_PIX_FMT_RGB24;
enum AVPixelFormat dst_pix_fmt = AV_PIX_FMT_YUV420P;
int ret;
int size;
const int RGBLinesize[1] = { 3 * (int)width };
pFrameYUV = av_frame_alloc();
pFrameYUV->width = width;
pFrameYUV->height = height;
pFrameYUV->format = dst_pix_fmt;
// Initialize pFrameYUV linesize
ret = av_image_alloc(pFrameYUV->data, pFrameYUV->linesize, pFrameYUV->width, pFrameYUV->height, AV_PIX_FMT_YUV420P, 1);
getLogger()->info("ImageDecoder:{} width={} height={} linesize[0]={} linesize[1]={} linesize[2]={}",
__func__, pFrameYUV->width, pFrameYUV->height, pFrameYUV->linesize[0], pFrameYUV->linesize[1], pFrameYUV->linesize[2]);
size = av_image_get_buffer_size(AV_PIX_FMT_YUV420P, pFrameYUV->width, pFrameYUV->height, 1);
imgCtx = sws_getCachedContext(imgCtx,
width,
height,
AV_PIX_FMT_RGB24,
pFrameYUV->width,
pFrameYUV->height,
AV_PIX_FMT_YUV420P,
SWS_BICUBIC, 0, 0, 0);
if( imgCtx == NULL)
{
getLogger()->error("ERROR: ImageDecoder: {} Cannot initialize the conversion context", __func__);
}
sws_scale(imgCtx,
(const uint8_t* const*)&src,
RGBLinesize,
0,
height,
pFrameYUV->data,
pFrameYUV->linesize);
memcpy(dest, &pFrameYUV->data[0], size);
sws_freeContext(imgCtx);
av_free(pFrameYUV);
}
I hope it helps you.
I am converting YUV444 decoded frames to RGBA format.
AVFrame* RGBFrame = av_frame_alloc();
RGBFrame->width = YUV_frame->width; RGBFrame->format = AV_PIX_FMT_RGBA;
RGBFrame->height = YUV_frame->height;
int ret = av_image_alloc(RGBFrame->data, RGBFrame->linesize, RGBFrame->width, RGBFrame->height, AV_PIX_FMT_RGBA, YUV_frame->pict_type);
if (ret < 0)
return false;
SwsContext* sws_Context = NULL;
sws_Context = sws_getCachedContext(sws_Context, YUV_frame->width, YUV_frame->height, pVideoCodecCtx->pix_fmt,
YUV_frame->width, YUV_frame->height, AV_PIX_FMT_RGBA, SWS_BILINEAR, NULL, NULL, NULL);
if (sws_Context == NULL) return false;
int result = sws_scale(sws_Context, YUV_frame->data, YUV_frame->linesize, 0, (int)YUV_frame->height, RGBFrame->data, RGBFrame->linesize);
if (result < 0) return false;
if (RGBFrame == NULL) {
av_frame_unref(RGBFrame);
return false;
}
sws_freeContext(sws_Context);
int ImageDecoder::rgb2yuv(uint8_t *src,
uint8_t *dest,
uint32_t *outBufferSize,
uint32_t width,
uint32_t height)
{
struct SwsContext *imgCtx = NULL;
uint8_t * RGBData[1] = {src};
const int RGBLinesize[1] = {3 * (int) width};
uint8_t * YUVData[] = {dest,
YUVData[0] + ((int) width * (int) height),
YUVData[1] + (((int) width * (int) height) / 4)};
const int YUVLinesize[] = {(int) width, (int) width / 2, (int) width / 2};
int size;
size = av_image_get_buffer_size(AV_PIX_FMT_YUV420P, width, height, 1);
*outBufferSize = size;
imgCtx = sws_getCachedContext(imgCtx,
width,
height,
AV_PIX_FMT_RGB24,
width,
height,
AV_PIX_FMT_YUV420P,
SWS_BICUBIC, 0, 0, 0);
if (imgCtx == NULL)
{
getLogger()->error("ERROR: ImageDecoder: {} Cannot initialize the conversion context", __func__);
return -1;
}
sws_scale(imgCtx,
RGBData,
RGBLinesize,
0,
height,
YUVData,
YUVLinesize);
sws_freeContext(imgCtx);
return 0;
}

ffmpeg filter dev get_video_buffer function usage

I'm writing a mosaic ffmpeg filter.
copy code from vf_vflip.c, I register a callback function get_video_buffer
and implement it as follows:
static AVFrame *get_video_buffer(AVFilterLink *link, int w, int h)
{
MosaicContext *s = link->dst->priv;
AVFrame *frame;
int i;
int j,k;
frame = ff_get_video_buffer(link->dst->outputs[0], w, h);
if (!frame)
return NULL;
if (s->w == 0 || s->h == 0)
return frame;
for (i = 0; i < 3; i ++) {
// some trick code
}
return frame;
}
static const AVFilterPad avfilter_vf_mosaic_inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
//.get_video_buffer = get_video_buffer,
.filter_frame = filter_frame,
.config_props = config_input,
},
{ NULL }
};
But after read some filter dev guide, I found that only a few filter implement get_video_buffer funcition.The default function is f_default_get_video_buffer()
I make some log find that ffmpeg call function like
get_video_buffer
filter_frame
get_video_buffer
filter_frame
get_video_buffer
filter_frame
...
I'm confused about get_video_buffer do what job.
Only know that some filter will hold frame cache.
Can I juse comment out the get_video_buffer hook?
I see flip job both in get_video_buffer() and filter_frame() in vf_vflip.c
Is it a waste of time?
static AVFrame *get_video_buffer(AVFilterLink *link, int w, int h)
{
FlipContext *flip = link->dst->priv;
AVFrame *frame;
int i;
frame = ff_get_video_buffer(link->dst->outputs[0], w, h);
if (!frame)
return NULL;
for (i = 0; i < 4; i ++) {
int vsub = i == 1 || i == 2 ? flip->vsub : 0;
int height = AV_CEIL_RSHIFT(h, vsub);
if (frame->data[i]) {
frame->data[i] += (height - 1) * frame->linesize[i];
frame->linesize[i] = -frame->linesize[i];
}
}
return frame;
}
static int filter_frame(AVFilterLink *link, AVFrame *frame)
{
FlipContext *flip = link->dst->priv;
int i;
for (i = 0; i < 4; i ++) {
int vsub = i == 1 || i == 2 ? flip->vsub : 0;
int height = AV_CEIL_RSHIFT(link->h, vsub);
if (frame->data[i]) {
frame->data[i] += (height - 1) * frame->linesize[i];
frame->linesize[i] = -frame->linesize[i];
}
}
return ff_filter_frame(link->dst->outputs[0], frame);
}

ffmpeg record change color

Im try record video from screen, for write to video file im use ffmpeg(libavcodec). But on result i see other colors, my example:
AVCodec *codec;
AVCodecContext *c= NULL;
AVStream *video_stream;
AVOutputFormat *out;
AVFormatContext *out_context;
int i, ret, x, y, got_output;
AVFrame *frame;
AVPacket pkt;
uint8_t endcode[] = { 0, 0, 1, 0xb7 };
printf("Encode video file %s\n", filename);
out = av_guess_format(NULL, filename, NULL);
if (!out) {
std::cout << "Could not deduce output format from file extension: using MPEG.\n" << filename << std::endl;
out = av_guess_format("mpeg", filename, NULL);
}
if (!out) {
std::cout << "Could not find suitable output format\n" << std::endl;
return;
}
out->video_codec = (AVCodecID)codec_id;
out_context = avformat_alloc_context();
if (!out_context) {
std::cout << "Memory error\n";
return;
}
out_context->oformat = out;
codec = avcodec_find_encoder((AVCodecID)codec_id);
if (!codec) {
fprintf(stderr, "Codec not found\n");
exit(1);
}
video_stream = avformat_new_stream(out_context, codec);
if (!video_stream) {
std::cout << "Could not alloc stream\n";
return;
}
c = video_stream->codec;
if (!c) {
fprintf(stderr, "Could not allocate video codec context\n");
exit(1);
}
c->bit_rate = 20000000;
c->width = rect_width;
c->height = rect_height;
c->time_base = (AVRational){1,25};
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);
if (avcodec_open2(c, codec, NULL) < 0) {
fprintf(stderr, "Could not open codec\n");
exit(1);
}
avio_open2(&out_context->pb, filename, AVIO_FLAG_WRITE, NULL, NULL );
avformat_write_header(out_context, 0);
frame = av_frame_alloc();
if (!frame) {
fprintf(stderr, "Could not allocate video frame\n");
exit(1);
}
frame->format = c->pix_fmt;
frame->width = c->width;
frame->height = c->height;
ret = av_image_alloc(frame->data, frame->linesize, c->width, c->height,
c->pix_fmt, 32);
if (ret < 0) {
fprintf(stderr, "Could not allocate raw picture buffer\n");
exit(1);
}
fprintf(stderr, "*0\n");
SwsContext *m_imageConvertContext = 0;
fprintf(stderr, "*0.1\n");
printf("size %3d %5d\n", rect_width, rect_height);
if ((rect_width % 4 != 0 && rect_width % 8 != 0 && rect_width % 16 != 0)
|| (rect_height % 4 != 0 && rect_height % 8 != 0 && rect_height % 16 != 0)) {
fprintf(stderr, "Video size dimensions must be multiple of 4,8 or 16.");
return;
}
m_imageConvertContext = sws_getCachedContext(m_imageConvertContext, frame->width, frame->height,AV_PIX_FMT_0RGB32, frame->width, frame->height, c->pix_fmt, SWS_BILINEAR, NULL, NULL, NULL);
fprintf(stderr, "*0.2\n");
int pts = 0;
for (i = 0; i < 25 * 20; i++) {
QImage image = QGuiApplication::primaryScreen()->grabWindow(0, rect_x, rect_y, rect_width, rect_height).toImage().convertToFormat(QImage::Format_RGB32);
pts ++;
av_init_packet(&pkt);
pkt.data = NULL; // packet data will be allocated by the encoder
pkt.size = 0;
fflush(stdout);
uint8_t *srcplanes[AV_NUM_DATA_POINTERS];
srcplanes[0]=(uint8_t*)image.bits();
srcplanes[1]=0;
srcplanes[2]=0;
srcplanes[3]=0;
srcplanes[4]=0;
srcplanes[5]=0;
srcplanes[6]=0;
srcplanes[7]=0;
int srcstride[AV_NUM_DATA_POINTERS];
srcstride[0]=image.bytesPerLine();
srcstride[1]=0;
srcstride[2]=0;
srcstride[3]=0;
srcstride[4]=0;
srcstride[5]=0;
srcstride[6]=0;
srcstride[7]=0;
int res = sws_scale(m_imageConvertContext, srcplanes, srcstride, 0,frame->height, frame->data, frame->linesize);
frame->pts = pts;
ret = avcodec_encode_video2(c, &pkt, frame, &got_output);
if (ret < 0) {
fprintf(stderr, "Error encoding frame\n");
exit(1);
}
if (got_output) {
printf("Write frame %3d (size=%5d)\n", i, pkt.size);
av_write_frame(out_context,&pkt);
av_free_packet(&pkt);
}
}
for (got_output = 1; got_output; i++) {
fflush(stdout);
ret = avcodec_encode_video2(c, &pkt, NULL, &got_output);
if (ret < 0) {
fprintf(stderr, "Error encoding frame\n");
exit(1);
}
if (got_output) {
printf("Write frame %3d (size=%5d)\n", i, pkt.size);
av_interleaved_write_frame(out_context, &pkt);
av_free_packet(&pkt);
}
}
av_write_trailer(out_context);
avio_close(out_context->pb);
avcodec_close(c);
av_free(c);
av_freep(&frame->data[0]);
av_frame_free(&frame);
resolution 1920x1080. On original display look this http://joxi.ru/p27bbn6u093elm
on save video colors is a dimmer http://joxi.ru/YmE99W1fZvbdWm
It seems, white background color changes to gray. Or may be it is brightness. What im do is wrong? How i can save to color ?
UDP
im try use
int *inv_table, srcRange, *table, dstRange , brightness, contrast, saturation;
int ret = sws_getColorspaceDetails(m_imageConvertContext, &inv_table, &srcRange, &table, &dstRange, &brightness, &contrast, &saturation);
sws_setColorspaceDetails(m_imageConvertContext, sws_getCoefficients(SWS_CS_DEFAULT), srcRange, sws_getCoefficients(SWS_CS_ITU709), dstRange, brightness, contrast, saturation);
but this is never change

How to get picture buffer data in ffmpeg?

I'm trying to pass bitmap from ffmpeg to android.
It already works but it's displaying picture right on surface passed from java to native code.
How can i get frame buffer bitmap data to pass it to java?
I've tried to save out_frame buffer data:
unsigned char bmpFileHeader[14] = {'B', 'M', 0,0,0,0, 0,0, 0,0, 54, 0,0,0};
unsigned char bmpInfoHeader[40] = {40,0,0,0, 0,0,0,0, 0,0,0,0, 1,0, 24,0};
unsigned char bmpPad[3] = {0, 0, 0};
void saveBuffer(int fileIndex, int width, int height, unsigned char *buffer, int buffer_size) {
unsigned char filename[1024];
sprintf(filename, "/storage/sdcard0/3d_player_%d.bmp", fileIndex);
LOGI(10, "saving ffmpeg bitmap file: %d to %s", fileIndex, filename);
FILE *bitmapFile = fopen(filename, "wb");
if (!bitmapFile) {
LOGE(10, "failed to create ffmpeg bitmap file");
return;
}
unsigned char filesize = 54 + 3 * width * height; // 3 = (r,g,b)
bmpFileHeader[2] = (unsigned char)(filesize);
bmpFileHeader[3] = (unsigned char)(filesize >> 8);
bmpFileHeader[4] = (unsigned char)(filesize >> 16);
bmpFileHeader[5] = (unsigned char)(filesize >> 24);
bmpInfoHeader[4] = (unsigned char)(width);
bmpInfoHeader[5] = (unsigned char)(width >> 8);
bmpInfoHeader[6] = (unsigned char)(width >> 16);
bmpInfoHeader[7] = (unsigned char)(width >> 24);
bmpInfoHeader[8] = (unsigned char)(height);
bmpInfoHeader[9] = (unsigned char)(height >> 8);
bmpInfoHeader[10] = (unsigned char)(height >> 16);
bmpInfoHeader[11] = (unsigned char)(height >> 24);
fwrite(bmpFileHeader, 1, 14, bitmapFile);
fwrite(bmpInfoHeader, 1, 40, bitmapFile);
int i;
for (i=0; i<height; i++) {
fwrite(buffer + width * (height - 1) * 3, 3, width, bitmapFile);
fwrite(bmpPad, 1, (4-(width * 3) % 4) % 4, bitmapFile);
}
fflush(bitmapFile);
fclose(bitmapFile);
}
int player_decode_video(struct DecoderData * decoder_data, JNIEnv * env,
struct PacketData *packet_data) {
int got_frame_ptr;
struct Player *player = decoder_data->player;
int stream_no = decoder_data->stream_no;
AVCodecContext * ctx = player->input_codec_ctxs[stream_no];
AVFrame * frame = player->input_frames[stream_no];
AVStream * stream = player->input_streams[stream_no];
int interrupt_ret;
int to_write;
int err = 0;
AVFrame *rgb_frame = player->rgb_frame;
ANativeWindow_Buffer buffer;
ANativeWindow * window;
#ifdef MEASURE_TIME
struct timespec timespec1, timespec2, diff;
#endif // MEASURE_TIME
LOGI(10, "player_decode_video decoding");
int frameFinished;
#ifdef MEASURE_TIME
clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &timespec1);
#endif // MEASURE_TIME
int ret = avcodec_decode_video2(ctx, frame, &frameFinished,
packet_data->packet);
#ifdef MEASURE_TIME
clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &timespec2);
diff = timespec_diff(timespec1, timespec2);
LOGI(3, "decode_video timediff: %d.%9ld", diff.tv_sec, diff.tv_nsec);
#endif // MEASURE_TIME
if (ret < 0) {
LOGE(1, "player_decode_video Fail decoding video %d\n", ret);
return -ERROR_WHILE_DECODING_VIDEO;
}
if (!frameFinished) {
LOGI(10, "player_decode_video Video frame not finished\n");
return 0;
}
// saving in buffer converted video frame
LOGI(7, "player_decode_video copy wait");
#ifdef MEASURE_TIME
clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &timespec1);
#endif // MEASURE_TIME
pthread_mutex_lock(&player->mutex_queue);
window = player->window;
if (window == NULL) {
pthread_mutex_unlock(&player->mutex_queue);
goto skip_frame;
}
ANativeWindow_setBuffersGeometry(window, ctx->width, ctx->height,
WINDOW_FORMAT_RGBA_8888);
if (ANativeWindow_lock(window, &buffer, NULL) != 0) {
pthread_mutex_unlock(&player->mutex_queue);
goto skip_frame;
}
pthread_mutex_unlock(&player->mutex_queue);
int format = buffer.format;
if (format < 0) {
LOGE(1, "Could not get window format")
}
enum PixelFormat out_format;
if (format == WINDOW_FORMAT_RGBA_8888) {
out_format = PIX_FMT_RGBA;
LOGI(6, "Format: WINDOW_FORMAT_RGBA_8888");
} else if (format == WINDOW_FORMAT_RGBX_8888) {
out_format = PIX_FMT_RGB0;
LOGE(1, "Format: WINDOW_FORMAT_RGBX_8888 (not supported)");
} else if (format == WINDOW_FORMAT_RGB_565) {
out_format = PIX_FMT_RGB565;
LOGE(1, "Format: WINDOW_FORMAT_RGB_565 (not supported)");
} else {
LOGE(1, "Unknown window format");
}
avpicture_fill((AVPicture *) rgb_frame, buffer.bits, out_format,
buffer.width, buffer.height);
rgb_frame->data[0] = buffer.bits;
if (format == WINDOW_FORMAT_RGBA_8888) {
rgb_frame->linesize[0] = buffer.stride * 4;
} else {
LOGE(1, "Unknown window format");
}
LOGI(6,
"Buffer: width: %d, height: %d, stride: %d",
buffer.width, buffer.height, buffer.stride);
int i = 0;
#ifdef MEASURE_TIME
clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &timespec2);
diff = timespec_diff(timespec1, timespec2);
LOGI(1,
"lockPixels and fillimage timediff: %d.%9ld", diff.tv_sec, diff.tv_nsec);
#endif // MEASURE_TIME
#ifdef MEASURE_TIME
clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &timespec1);
#endif // MEASURE_TIME
LOGI(7, "player_decode_video copying...");
AVFrame * out_frame;
int rescale;
if (ctx->width == buffer.width && ctx->height == buffer.height) {
// This always should be true
out_frame = rgb_frame;
rescale = FALSE;
} else {
out_frame = player->tmp_frame2;
rescale = TRUE;
}
if (ctx->pix_fmt == PIX_FMT_YUV420P) {
__I420ToARGB(frame->data[0], frame->linesize[0], frame->data[2],
frame->linesize[2], frame->data[1], frame->linesize[1],
out_frame->data[0], out_frame->linesize[0], ctx->width,
ctx->height);
} else if (ctx->pix_fmt == PIX_FMT_NV12) {
__NV21ToARGB(frame->data[0], frame->linesize[0], frame->data[1],
frame->linesize[1], out_frame->data[0], out_frame->linesize[0],
ctx->width, ctx->height);
} else {
LOGI(3, "Using slow conversion: %d ", ctx->pix_fmt);
struct SwsContext *sws_context = player->sws_context;
sws_context = sws_getCachedContext(sws_context, ctx->width, ctx->height,
ctx->pix_fmt, ctx->width, ctx->height, out_format,
SWS_FAST_BILINEAR, NULL, NULL, NULL);
player->sws_context = sws_context;
if (sws_context == NULL) {
LOGE(1, "could not initialize conversion context from: %d"
", to :%d\n", ctx->pix_fmt, out_format);
// TODO some error
}
sws_scale(sws_context, (const uint8_t * const *) frame->data,
frame->linesize, 0, ctx->height, out_frame->data,
out_frame->linesize);
}
if (rescale) {
// Never occurs
__ARGBScale(out_frame->data[0], out_frame->linesize[0], ctx->width,
ctx->height, rgb_frame->data[0], rgb_frame->linesize[0],
buffer.width, buffer.height, __kFilterNone);
out_frame = rgb_frame;
}
// TODO: (4ntoine) frame decoded and rescaled, ready to call callback with frame picture from buffer
int bufferSize = buffer.width * buffer.height * 3; // 3 = (r,g,b);
static int bitmapCounter = 0;
if (bitmapCounter < 10) {
saveBuffer(bitmapCounter++, buffer.width, buffer.height, (unsigned char *)out_frame->data, bufferSize);
}
but out_frame is empty and file has header and 0x00 bytes body.
How to get picture buffer data in ffmpeg?
Solved, in short: you should take buffer from ANativeWindow_Buffer - buffer.bits. Pay attention buffer is (rgba) but BMP is usually (rgb) - 3 bytes. To save it as BMP one need to add BMP header and save lines with padding.

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