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Read video I/P/B frames.

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This commit is contained in:
Alf
2020-11-11 20:33:25 -08:00
parent 0d64e128a2
commit bc92e81a2c
2 changed files with 44 additions and 26 deletions
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49
src/ffprobe-wasm-wrapper.cpp
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@@ -128,7 +128,7 @@ FileInfoResponse get_file_info() {
return r;
}
FramesResponse get_frames() {
FramesResponse get_frames(int offset) {
av_log_set_level(AV_LOG_QUIET); // No logging output for libav.
FILE *file = fopen("file", "rb");
@@ -190,22 +190,39 @@ FramesResponse get_frames() {
AVPacket *pPacket = av_packet_alloc();
AVFrame *pFrame = av_frame_alloc();
int how_many_packets_to_process = 100;
// av_seek_frame(pFormatContext, 1, 1001*30, AVSEEK_FLAG_ANY);
while (av_read_frame(pFormatContext, pPacket) >= 0) {
if (pPacket->stream_index == video_stream_index) {
int how_many_packets_to_process = 300;
int frame_count = 0;
avcodec_send_packet(pCodecContext, pPacket);
avcodec_receive_frame(pCodecContext, pFrame);
Frame f = {
.pict_type = (char) av_get_picture_type_char(pFrame->pict_type),
.frame_number = pCodecContext->frame_number,
.pkt_size = pFrame->pkt_size,
};
r.frames.push_back(f);
// Read video frames.
// TODO: Support seek so we don't have to cap at 300 frames.
while (av_read_frame(pFormatContext, pPacket) >= 0) {
if (frame_count >= offset) {
if (pPacket->stream_index == video_stream_index) {
int response = 0;
response = avcodec_send_packet(pCodecContext, pPacket);
if (response >= 0) {
response = avcodec_receive_frame(pCodecContext, pFrame);
if (response == AVERROR(EAGAIN) || response == AVERROR_EOF) {
continue;
}
Frame f = {
.pict_type = (char) av_get_picture_type_char(pFrame->pict_type),
.frame_number = pCodecContext->frame_number,
.pkt_size = pFrame->pkt_size,
};
r.frames.push_back(f);
if (--how_many_packets_to_process <= 0) break;
}
}
}
if (--how_many_packets_to_process <= 0) break;
frame_count++;
}
return r;
}
@@ -234,9 +251,9 @@ EMSCRIPTEN_BINDINGS(FileInfoResponse_struct) {
register_vector<Stream>("Stream");
emscripten::value_object<Frame>("Frame")
.field("frame_type", &Frame::pict_type)
.field("pict_type", &Frame::pict_type)
.field("frame_number", &Frame::frame_number)
.field("frame_size", &Frame::pkt_size);
.field("pkt_size", &Frame::pkt_size);
register_vector<Frame>("Frame");
emscripten::value_object<FileInfoResponse>("FileInfoResponse")