aculnaig
Reputation: 43
ffmpeg: libavfilter API av_buffersink_get_frame returns alway EAGAIN
I want to resize an image with libavfilter C API through zscale filter and libplacebo filter but no matter how I call av_buffersink_get_frame, it always returns EAGAIN and no data is filled in the filtered_frame.
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <libgen.h>
#include <libavcodec/avcodec.h>
#include <libavformat/avformat.h>
#include <libavfilter/avfilter.h>
#include <libavfilter/buffersrc.h>
#include <libavfilter/buffersink.h>
#include <libavutil/log.h>
int main(int argc, char **argv)
{
if (argc != 2) {
fprintf(stderr, "usage: %s <filename>\n", argv[0]);
exit(EXIT_FAILURE);
}
const char *src_name = argv[1];
const char *dst_name = basename(src_name);
int ret = 0;
const enum AVPixelFormat src_format = AV_PIX_FMT_YUV422P;
av_log_set_level(AV_LOG_TRACE);
AVFormatContext *fmt_ctx = avformat_alloc_context();
if (fmt_ctx == NULL) {
av_log(NULL, AV_LOG_TRACE, "avformat_alloc_context(): failed.\n");
exit(EXIT_SUCCESS);
}
if ((ret = avformat_open_input(&fmt_ctx, src_name, NULL, NULL)) != 0) {
av_log(NULL, AV_LOG_TRACE, "avformat_open_input(): %s.\n", av_err2str(ret));
exit(EXIT_SUCCESS);
}
AVCodecContext *dec_ctx;
AVCodec *dec;
if ((ret = av_find_best_stream(fmt_ctx, AVMEDIA_TYPE_VIDEO, -1, -1, &dec, 0)) < 0) {
av_log(NULL, AV_LOG_TRACE, "av_find_best_stream(): %s.\n", av_err2str(ret));
exit(EXIT_SUCCESS);
}
dec_ctx = avcodec_alloc_context3(dec);
if (dec_ctx == NULL) {
av_log(NULL, AV_LOG_TRACE, "avcodec_alloc_context3(): failed.\n");
exit(EXIT_SUCCESS);
}
if ((ret = avcodec_open2(dec_ctx, dec, NULL)) < 0) {
av_log(NULL, AV_LOG_TRACE, "avcodec_open2(): %s.\n", av_err2str(ret));
exit(EXIT_SUCCESS);
}
AVFrame *frame = av_frame_alloc();
if (frame == NULL) {
av_log(NULL, AV_LOG_TRACE, "av_frame_alloc(): failed.\n");
exit(EXIT_SUCCESS);
}
AVPacket *packet = av_packet_alloc();
if (packet == NULL) {
av_log(NULL, AV_LOG_TRACE, "av_packet_alloc(): failed.\n");
exit(EXIT_SUCCESS);
}
if ((ret = av_read_frame(fmt_ctx, packet)) < 0) {
av_log(NULL, AV_LOG_TRACE, "av_read_frame(): %s.\n", av_err2str(ret));
exit(EXIT_SUCCESS);
}
ret = avcodec_send_packet(dec_ctx, packet);
if (ret == AVERROR(EAGAIN)) {
av_log(NULL, AV_LOG_TRACE, "avcodec_send_packet(): %s.\n", av_err2str(ret));
avcodec_receive_frame(dec_ctx, frame);
avcodec_send_packet(dec_ctx, packet);
}
if ((ret = avcodec_receive_frame(dec_ctx, frame)) < 0) {
av_log(NULL, AV_LOG_TRACE, "avcodec_receive_frame(): %s.\n", av_err2str(ret));
exit(EXIT_SUCCESS);
}
av_packet_unref(packet);
av_log(NULL, AV_LOG_TRACE, "filename: %s, w: %d, h: %d, fmt: %d\n", src_name, frame->width, frame->height, frame->format);
AVFilterGraph *filter_graph = avfilter_graph_alloc();
char buffersrc_args[512];
snprintf(buffersrc_args, sizeof(buffersrc_args), "video_size=%dx%d:pix_fmt=%d:time_base=1/25", frame->width, frame->height, frame->format);
AVFilterContext *buffersrc_ctx;
if ((ret = avfilter_graph_create_filter(&buffersrc_ctx, avfilter_get_by_name("buffer"), NULL, buffersrc_args, NULL, filter_graph)) < 0) {
av_log(NULL, AV_LOG_TRACE, "avfilter_graph_create_filter(): %s.\n", av_err2str(ret));
exit(EXIT_SUCCESS);
}
char libplacebo_args[512];
snprintf(libplacebo_args, sizeof(libplacebo_args), "format=yuv420p:colorspace=bt470bg:color_primaries=bt709:color_trc=iec61966-2-1:range=pc:w=(iw/2):h=(ih/2):downscaler=none:dithering=none");
AVFilterContext *libplacebo_ctx;
if ((ret = avfilter_graph_create_filter(&libplacebo_ctx, avfilter_get_by_name("libplacebo"), NULL, libplacebo_args, NULL, filter_graph)) < 0) {
av_log(NULL, AV_LOG_TRACE, "avfilter_graph_create_filter(): %s.\n", av_err2str(ret));
exit(EXIT_SUCCESS);
}
AVFilterContext *buffersink_ctx;
if ((ret = avfilter_graph_create_filter(&buffersink_ctx, avfilter_get_by_name("buffersink"), NULL, NULL, NULL, filter_graph)) < 0) {
av_log(NULL, AV_LOG_TRACE, "avfilter_graph_create_filter(): %s.\n", av_err2str(ret));
exit(EXIT_SUCCESS);
}
if ((ret = avfilter_link(buffersrc_ctx, 0, libplacebo_ctx, 0)) != 0) {
av_log(NULL, AV_LOG_TRACE, "avfilter_link(): %s.\n", av_err2str(ret));
exit(EXIT_SUCCESS);
}
if ((ret = avfilter_link(libplacebo_ctx, 0, buffersink_ctx, 0)) != 0) {
av_log(NULL, AV_LOG_TRACE, "avfilter_link(): %s.\n", av_err2str(ret));
exit(EXIT_SUCCESS);
}
if ((ret = avfilter_graph_config(filter_graph, NULL)) < 0) {
av_log(NULL, AV_LOG_TRACE, "avfilter_graph_config(): %s.\n", av_err2str(ret));
exit(EXIT_SUCCESS);
}
AVFrame *filtered_frame = av_frame_alloc();
if (filtered_frame == NULL) {
av_log(NULL, AV_LOG_TRACE, "av_frame_alloc(): failed.\n");
exit(EXIT_SUCCESS);
}
if ((ret = av_buffersrc_add_frame(buffersrc_ctx, frame)) < 0) {
av_log(NULL, AV_LOG_TRACE, "av_buffersrc_add_frame(): %s.\n", av_err2str(ret));
exit(EXIT_SUCCESS);
}
while (1) {
int ret = av_buffersink_get_frame(buffersink_ctx, filtered_frame);
if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF)
break;
if (ret < 0) {
av_log(NULL, AV_LOG_TRACE, "av_buffersink_get_frame(): %s.\n", av_err2str(ret));
exit(EXIT_FAILURE);
}
}
av_log(NULL, AV_LOG_TRACE, "filename: %s, w: %d, h: %d, f: %d\n", dst_name, filtered_frame->width, filtered_frame->height, filtered_frame->format);
AVCodecContext *enc_ctx;
AVCodec *enc;
AVPacket *enc_packet = av_packet_alloc();
enc = avcodec_find_encoder_by_name("mjpeg");
enc_ctx = avcodec_alloc_context3(enc);
enc_ctx->width = filtered_frame->width;
enc_ctx->height = filtered_frame->height;
enc_ctx->bit_rate = dec_ctx->bit_rate * 1024;
enc_ctx->time_base = (AVRational) {1, 25};
enc_ctx->framerate = (AVRational) {25, 1};
enc_ctx->pix_fmt = filtered_frame->format;
enc_ctx->strict_std_compliance = FF_COMPLIANCE_EXPERIMENTAL;
enc_ctx->compression_level = 0;
enc_ctx->color_range = AVCOL_RANGE_JPEG;
avcodec_open2(enc_ctx, enc, NULL);
avcodec_send_frame(enc_ctx, filtered_frame);
avcodec_receive_packet(enc_ctx, enc_packet);
FILE *dst_file = fopen(dst_name, "wb");
fwrite(enc_packet->data, 1, enc_packet->size, dst_file);
fclose(dst_file);
av_packet_unref(enc_packet);
av_frame_free(&frame);
av_frame_free(&filtered_frame);
avfilter_graph_free(&filter_graph);
avformat_close_input(&fmt_ctx);
avformat_free_context(fmt_ctx);
exit(EXIT_SUCCESS);
}
and here are the logs
PS: the logs were so many I could paste in stackoverflow
Upvotes: 2
Views: 133