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Read frames from file and add to table.

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This commit is contained in:
Alf
2020-11-10 19:58:11 -08:00
parent 623f1dad7c
commit 0d64e128a2
4 changed files with 150 additions and 16 deletions
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110
src/ffprobe-wasm-wrapper.cpp
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@@ -34,6 +34,12 @@ typedef struct Stream {
int frame_size;
} Stream;
typedef struct Frame {
char pict_type;
int frame_number;
int pkt_size;
} Frame;
typedef struct FileInfoResponse {
std::string name;
int bit_rate;
@@ -44,6 +50,10 @@ typedef struct FileInfoResponse {
std::vector<Stream> streams;
} FileInfoResponse;
typedef struct FramesResponse {
std::vector<Frame> frames;
} FramesResponse;
FileInfoResponse get_file_info() {
FILE *file = fopen("file", "rb");
if (!file) {
@@ -79,11 +89,11 @@ FileInfoResponse get_file_info() {
};
// Get streams data.
AVCodec *pCodec = NULL;
AVCodecParameters *pCodecParameters = NULL;
int video_stream_index = -1;
// AVCodec *pCodec = NULL;
// AVCodecParameters *pCodecParameters = NULL;
// int video_stream_index = -1;
// Loop through the streams and print its information.
// Loop through the streams.
for (int i = 0; i < pFormatContext->nb_streams; i++) {
AVCodecParameters *pLocalCodecParameters = NULL;
pLocalCodecParameters = pFormatContext->streams[i]->codecpar;
@@ -118,6 +128,87 @@ FileInfoResponse get_file_info() {
return r;
}
FramesResponse get_frames() {
av_log_set_level(AV_LOG_QUIET); // No logging output for libav.
FILE *file = fopen("file", "rb");
if (!file) {
printf("cannot open file\n");
}
fclose(file);
AVFormatContext *pFormatContext = avformat_alloc_context();
if (!pFormatContext) {
printf("ERROR: could not allocate memory for Format Context\n");
}
// Open the file and read header.
int ret;
if ((ret = avformat_open_input(&pFormatContext, "file", NULL, NULL)) < 0) {
printf("ERROR: could not open the file. Error: %d\n", ret);
printf("%s", av_err2str(ret));
}
// Get stream info from format.
if (avformat_find_stream_info(pFormatContext, NULL) < 0) {
printf("ERROR: could not get stream info\n");
}
// Get streams data.
AVCodec *pCodec = NULL;
AVCodecParameters *pCodecParameters = NULL;
int video_stream_index = -1;
// Loop through the streams.
for (int i = 0; i < pFormatContext->nb_streams; i++) {
AVCodecParameters *pLocalCodecParameters = NULL;
pLocalCodecParameters = pFormatContext->streams[i]->codecpar;
// Print out the decoded frame info.
AVCodec *pLocalCodec = avcodec_find_decoder(pLocalCodecParameters->codec_id);
if (pLocalCodecParameters->codec_type == AVMEDIA_TYPE_VIDEO) {
if (video_stream_index == -1) {
video_stream_index = i;
pCodec = pLocalCodec;
pCodecParameters = pLocalCodecParameters;
}
printf("Video Codec: resolution %d x %d\n",
pLocalCodecParameters->width, pLocalCodecParameters->height);
} else if (pLocalCodecParameters->codec_type == AVMEDIA_TYPE_AUDIO) {
printf("Audio Codec: %d channels, sample rate %d\n",
pLocalCodecParameters->channels, pLocalCodecParameters->sample_rate);
}
}
FramesResponse r;
AVCodecContext *pCodecContext = avcodec_alloc_context3(pCodec);
avcodec_parameters_to_context(pCodecContext, pCodecParameters);
avcodec_open2(pCodecContext, pCodec, NULL);
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) {
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);
}
if (--how_many_packets_to_process <= 0) break;
}
return r;
}
EMSCRIPTEN_BINDINGS(my_constant_example) {
function("c_avformat_version", &c_avformat_version);
@@ -142,6 +233,12 @@ EMSCRIPTEN_BINDINGS(FileInfoResponse_struct) {
;
register_vector<Stream>("Stream");
emscripten::value_object<Frame>("Frame")
.field("frame_type", &Frame::pict_type)
.field("frame_number", &Frame::frame_number)
.field("frame_size", &Frame::pkt_size);
register_vector<Frame>("Frame");
emscripten::value_object<FileInfoResponse>("FileInfoResponse")
.field("name", &FileInfoResponse::name)
.field("duration", &FileInfoResponse::duration)
@@ -152,4 +249,9 @@ EMSCRIPTEN_BINDINGS(FileInfoResponse_struct) {
.field("streams", &FileInfoResponse::streams)
;
function("get_file_info", &get_file_info);
emscripten::value_object<FramesResponse>("FramesResponse")
.field("frames", &FramesResponse::frames)
;
function("get_frames", &get_frames);
}