mirror of https://github.com/odrling/Aegisub
563 lines
16 KiB
C++
563 lines
16 KiB
C++
// Copyright (c) 2007-2008 Fredrik Mellbin
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//
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// Permission is hereby granted, free of charge, to any person obtaining a copy
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// of this software and associated documentation files (the "Software"), to deal
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// in the Software without restriction, including without limitation the rights
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// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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// copies of the Software, and to permit persons to whom the Software is
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// furnished to do so, subject to the following conditions:
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//
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// The above copyright notice and this permission notice shall be included in
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// all copies or substantial portions of the Software.
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//
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// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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// THE SOFTWARE.
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#include "ffvideosource.h"
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#include <errno.h>
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int VideoBase::InitPP(const char *PP, int PixelFormat, char *ErrorMsg, unsigned MsgSize) {
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if (PP == NULL || !strcmp(PP, ""))
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return 0;
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PPMode = pp_get_mode_by_name_and_quality(PP, PP_QUALITY_MAX);
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if (!PPMode) {
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_snprintf(ErrorMsg, MsgSize, "Invalid postprocesing settings");
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return 1;
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}
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int Flags = GetCPUFlags();
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switch (PixelFormat) {
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case PIX_FMT_YUV420P: Flags |= PP_FORMAT_420; break;
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case PIX_FMT_YUV422P: Flags |= PP_FORMAT_422; break;
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case PIX_FMT_YUV411P: Flags |= PP_FORMAT_411; break;
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case PIX_FMT_YUV444P: Flags |= PP_FORMAT_444; break;
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default:
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_snprintf(ErrorMsg, MsgSize, "Input format is not supported for postprocessing");
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return 2;
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}
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PPContext = pp_get_context(VP.Width, VP.Height, Flags);
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if (!(PPFrame = avcodec_alloc_frame())) {
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_snprintf(ErrorMsg, MsgSize, "Failed to allocate temporary frame");
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return 3;
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}
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if (avpicture_alloc((AVPicture *)PPFrame, PixelFormat, VP.Width, VP.Height) < 0) {
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av_free(PPFrame);
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PPFrame = NULL;
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_snprintf(ErrorMsg, MsgSize, "Failed to allocate picture");
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return 4;
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}
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FinalFrame = PPFrame;
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return 0;
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}
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AVFrameLite *VideoBase::OutputFrame(AVFrame *Frame) {
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if (PPContext) {
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pp_postprocess(const_cast<const uint8_t **>(Frame->data), Frame->linesize, PPFrame->data, PPFrame->linesize, VP.Width, VP.Height, Frame->qscale_table, Frame->qstride, PPMode, PPContext, Frame->pict_type | (Frame->qscale_type ? PP_PICT_TYPE_QP2 : 0));
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PPFrame->key_frame = Frame->key_frame;
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PPFrame->pict_type = Frame->pict_type;
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}
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if (SWS) {
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sws_scale(SWS, PPFrame->data, PPFrame->linesize, 0, VP.Height, FinalFrame->data, FinalFrame->linesize);
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FinalFrame->key_frame = PPFrame->key_frame;
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FinalFrame->pict_type = PPFrame->pict_type;
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}
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return reinterpret_cast<AVFrameLite *>(FinalFrame);
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}
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VideoBase::VideoBase() {
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memset(&VP, 0, sizeof(VP));
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PPContext = NULL;
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PPMode = NULL;
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SWS = NULL;
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LastFrameNum = -1;
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CurrentFrame = 0;
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CodecContext = NULL;
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DecodeFrame = avcodec_alloc_frame();
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PPFrame = DecodeFrame;
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FinalFrame = PPFrame;
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}
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VideoBase::~VideoBase() {
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if (PPMode)
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pp_free_mode(PPMode);
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if (PPContext)
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pp_free_context(PPContext);
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if (SWS)
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sws_freeContext(SWS);
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if (FinalFrame != PPFrame) {
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avpicture_free((AVPicture *)FinalFrame);
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av_free(FinalFrame);
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}
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if (PPFrame != DecodeFrame) {
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avpicture_free((AVPicture *)PPFrame);
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av_free(PPFrame);
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}
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av_free(DecodeFrame);
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}
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AVFrameLite *VideoBase::GetFrameByTime(double Time, char *ErrorMsg, unsigned MsgSize) {
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int Frame = Frames.ClosestFrameFromDTS((Time * 1000 * Frames.TB.Den) / Frames.TB.Num);
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return GetFrame(Frame, ErrorMsg, MsgSize);
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}
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int VideoBase::SetOutputFormat(int TargetFormats, int Width, int Height, char *ErrorMsg, unsigned MsgSize) {
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// FIXME: investigate the possible bug in avcodec_find_best_pix_fmt
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// int Loss;
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// int OutputFormat = avcodec_find_best_pix_fmt(TargetFormats,
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// CodecContext->pix_fmt, 1 /* Required to prevent pointless RGB32 => RGB24 conversion */, &Loss);
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// if (OutputFormat == -1)
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// return -1;
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int OutputFormat = TargetFormats;
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SwsContext *NewSWS = NULL;
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if (CodecContext->pix_fmt != OutputFormat || Width != CodecContext->width || Height != CodecContext->height) {
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NewSWS = sws_getContext(CodecContext->width, CodecContext->height, CodecContext->pix_fmt, Width, Height,
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OutputFormat, GetCPUFlags() | SWS_BICUBIC, NULL, NULL, NULL);
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if (NewSWS == NULL) {
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_snprintf(ErrorMsg, MsgSize, "Failed to allocate SWScale context");
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return 1;
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}
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}
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if (SWS)
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sws_freeContext(SWS);
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SWS = NewSWS;
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VP.Height = Height;
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VP.Width = Width;
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VP.PixelFormat = OutputFormat;
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// FIXME: In theory the allocations in this part could fail just like in InitPP but whatever
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if (FinalFrame != PPFrame) {
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avpicture_free((AVPicture *)FinalFrame);
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av_free(FinalFrame);
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}
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if (SWS) {
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FinalFrame = avcodec_alloc_frame();
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avpicture_alloc((AVPicture *)FinalFrame, VP.PixelFormat, VP.Width, VP.Height);
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} else {
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FinalFrame = PPFrame;
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}
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return 0;
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}
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void VideoBase::ResetOutputFormat() {
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if (SWS)
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sws_freeContext(SWS);
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SWS = NULL;
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VP.Height = CodecContext->height;
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VP.Width = CodecContext->width;
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VP.PixelFormat = CodecContext->pix_fmt;
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}
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void FFVideoSource::Free(bool CloseCodec) {
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if (CloseCodec)
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avcodec_close(CodecContext);
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av_close_input_file(FormatContext);
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// how was it allocated? how was it deallocate? nobody knows
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//av_free(FormatContext);
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}
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FFVideoSource::FFVideoSource(const char *SourceFile, int Track, FrameIndex *TrackIndices,
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const char *PP, int Threads, int SeekMode, char *ErrorMsg, unsigned MsgSize) {
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FormatContext = NULL;
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AVCodec *Codec = NULL;
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this->SeekMode = SeekMode;
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VideoTrack = Track;
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Frames = (*TrackIndices)[VideoTrack];
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if (Frames.size() == 0) {
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_snprintf(ErrorMsg, MsgSize, "Video track contains no frames");
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throw ErrorMsg;
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}
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if (av_open_input_file(&FormatContext, SourceFile, NULL, 0, NULL) != 0) {
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_snprintf(ErrorMsg, MsgSize, "Couldn't open '%s'", SourceFile);
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throw ErrorMsg;
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}
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if (av_find_stream_info(FormatContext) < 0) {
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Free(false);
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_snprintf(ErrorMsg, MsgSize, "Couldn't find stream information");
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throw ErrorMsg;
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}
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if (SeekMode >= 0 && av_seek_frame(FormatContext, VideoTrack, Frames[0].DTS, AVSEEK_FLAG_BACKWARD) < 0) {
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Free(false);
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_snprintf(ErrorMsg, MsgSize, "Video track is unseekable");
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throw ErrorMsg;
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}
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CodecContext = FormatContext->streams[VideoTrack]->codec;
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CodecContext->thread_count = Threads;
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Codec = avcodec_find_decoder(CodecContext->codec_id);
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if (Codec == NULL) {
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Free(false);
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_snprintf(ErrorMsg, MsgSize, "Video codec not found");
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throw ErrorMsg;
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}
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if (avcodec_open(CodecContext, Codec) < 0) {
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Free(false);
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_snprintf(ErrorMsg, MsgSize, "Could not open video codec");
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throw ErrorMsg;
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}
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// Always try to decode a frame to make sure all required parameters are known
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int64_t Dummy;
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if (DecodeNextFrame(DecodeFrame, &Dummy, ErrorMsg, MsgSize)) {
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Free(true);
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throw ErrorMsg;
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}
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//VP.image_type = VideoInfo::IT_TFF;
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VP.Width = CodecContext->width;
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VP.Height = CodecContext->height;
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VP.FPSDenominator = FormatContext->streams[VideoTrack]->time_base.num;
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VP.FPSNumerator = FormatContext->streams[VideoTrack]->time_base.den;
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VP.NumFrames = Frames.size();
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VP.PixelFormat = CodecContext->pix_fmt;
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VP.FirstTime = ((Frames.front().DTS * Frames.TB.Num) / (double)Frames.TB.Den) / 1000;
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VP.LastTime = ((Frames.back().DTS * Frames.TB.Num) / (double)Frames.TB.Den) / 1000;
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if (VP.Width <= 0 || VP.Height <= 0) {
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Free(true);
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_snprintf(ErrorMsg, MsgSize, "Codec returned zero size video");
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throw ErrorMsg;
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}
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// sanity check framerate
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if (VP.FPSDenominator > VP.FPSNumerator || VP.FPSDenominator <= 0 || VP.FPSNumerator <= 0) {
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VP.FPSDenominator = 1;
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VP.FPSNumerator = 30;
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}
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if (InitPP(PP, CodecContext->pix_fmt, ErrorMsg, MsgSize)) {
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Free(true);
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throw ErrorMsg;
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}
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// Adjust framerate to match the duration of the first frame
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if (Frames.size() >= 2) {
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unsigned int DTSDiff = (unsigned int)FFMAX(Frames[1].DTS - Frames[0].DTS, 1);
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VP.FPSDenominator *= DTSDiff;
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}
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// Cannot "output" to PPFrame without doing all other initialization
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// This is the additional mess required for seekmode=-1 to work in a reasonable way
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OutputFrame(DecodeFrame);
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LastFrameNum = 0;
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// Set AR variables
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VP.SARNum = CodecContext->sample_aspect_ratio.num;
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VP.SARDen = CodecContext->sample_aspect_ratio.den;
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}
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FFVideoSource::~FFVideoSource() {
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Free(true);
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}
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int FFVideoSource::DecodeNextFrame(AVFrame *AFrame, int64_t *AStartTime, char *ErrorMsg, unsigned MsgSize) {
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AVPacket Packet;
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int FrameFinished = 0;
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*AStartTime = -1;
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while (av_read_frame(FormatContext, &Packet) >= 0) {
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if (Packet.stream_index == VideoTrack) {
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if (*AStartTime < 0)
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*AStartTime = Packet.dts;
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avcodec_decode_video(CodecContext, AFrame, &FrameFinished, Packet.data, Packet.size);
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}
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av_free_packet(&Packet);
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if (FrameFinished)
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goto Done;
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}
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// Flush the last frames
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if (CodecContext->has_b_frames)
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avcodec_decode_video(CodecContext, AFrame, &FrameFinished, NULL, 0);
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if (!FrameFinished)
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goto Error;
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// Ignore errors for now
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Error:
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Done:
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return 0;
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}
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AVFrameLite *FFVideoSource::GetFrame(int n, char *ErrorMsg, unsigned MsgSize) {
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// PPFrame always holds frame LastFrameNum even if no PP is applied
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if (LastFrameNum == n)
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return OutputFrame(DecodeFrame);
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bool HasSeeked = false;
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if (SeekMode >= 0) {
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int ClosestKF = Frames.FindClosestKeyFrame(n);
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if (SeekMode == 0) {
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if (n < CurrentFrame) {
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av_seek_frame(FormatContext, VideoTrack, Frames[0].DTS, AVSEEK_FLAG_BACKWARD);
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avcodec_flush_buffers(CodecContext);
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CurrentFrame = 0;
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}
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} else {
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// 10 frames is used as a margin to prevent excessive seeking since the predicted best keyframe isn't always selected by avformat
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if (n < CurrentFrame || ClosestKF > CurrentFrame + 10 || (SeekMode == 3 && n > CurrentFrame + 10)) {
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av_seek_frame(FormatContext, VideoTrack, (SeekMode == 3) ? Frames[n].DTS : Frames[ClosestKF].DTS, AVSEEK_FLAG_BACKWARD);
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avcodec_flush_buffers(CodecContext);
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HasSeeked = true;
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}
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}
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} else if (n < CurrentFrame) {
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_snprintf(ErrorMsg, MsgSize, "Non-linear access attempted");
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return NULL;
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}
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do {
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int64_t StartTime;
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if (DecodeNextFrame(DecodeFrame, &StartTime, ErrorMsg, MsgSize))
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return NULL;
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if (HasSeeked) {
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HasSeeked = false;
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// Is the seek destination time known? Does it belong to a frame?
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if (StartTime < 0 || (CurrentFrame = Frames.FrameFromDTS(StartTime)) < 0) {
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switch (SeekMode) {
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case 1:
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_snprintf(ErrorMsg, MsgSize, "Frame accurate seeking is not possible in this file");
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return NULL;
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case 2:
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case 3:
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CurrentFrame = Frames.ClosestFrameFromDTS(StartTime);
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break;
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default:
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_snprintf(ErrorMsg, MsgSize, "Failed assertion");
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return NULL;
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}
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}
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}
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CurrentFrame++;
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} while (CurrentFrame <= n);
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LastFrameNum = n;
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return OutputFrame(DecodeFrame);
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}
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void MatroskaVideoSource::Free(bool CloseCodec) {
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if (CS)
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cs_Destroy(CS);
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if (MC.ST.fp) {
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mkv_Close(MF);
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fclose(MC.ST.fp);
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}
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if (CloseCodec)
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avcodec_close(CodecContext);
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av_free(CodecContext);
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}
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MatroskaVideoSource::MatroskaVideoSource(const char *SourceFile, int Track,
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FrameIndex *TrackIndices, const char *PP,
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int Threads, char *ErrorMsg, unsigned MsgSize) {
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AVCodec *Codec = NULL;
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CodecContext = NULL;
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TrackInfo *TI = NULL;
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CS = NULL;
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VideoTrack = Track;
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Frames = (*TrackIndices)[VideoTrack];
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if (Frames.size() == 0) {
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_snprintf(ErrorMsg, MsgSize, "Video track contains no frames");
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throw ErrorMsg;
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}
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MC.ST.fp = fopen(SourceFile, "rb");
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if (MC.ST.fp == NULL) {
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_snprintf(ErrorMsg, MsgSize, "Can't open '%s': %s", SourceFile, strerror(errno));
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throw ErrorMsg;
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}
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setvbuf(MC.ST.fp, NULL, _IOFBF, CACHESIZE);
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MF = mkv_OpenEx(&MC.ST.base, 0, 0, ErrorMessage, sizeof(ErrorMessage));
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if (MF == NULL) {
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fclose(MC.ST.fp);
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_snprintf(ErrorMsg, MsgSize, "Can't parse Matroska file: %s", ErrorMessage);
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throw ErrorMsg;
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}
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mkv_SetTrackMask(MF, ~(1 << VideoTrack));
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TI = mkv_GetTrackInfo(MF, VideoTrack);
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if (TI->CompEnabled) {
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CS = cs_Create(MF, VideoTrack, ErrorMessage, sizeof(ErrorMessage));
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if (CS == NULL) {
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Free(false);
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_snprintf(ErrorMsg, MsgSize, "Can't create decompressor: %s", ErrorMessage);
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throw ErrorMsg;
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}
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}
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CodecContext = avcodec_alloc_context();
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CodecContext->extradata = (uint8_t *)TI->CodecPrivate;
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CodecContext->extradata_size = TI->CodecPrivateSize;
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CodecContext->thread_count = Threads;
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Codec = avcodec_find_decoder(MatroskaToFFCodecID(TI));
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if (Codec == NULL) {
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Free(false);
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_snprintf(ErrorMsg, MsgSize, "Video codec not found");
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throw ErrorMsg;
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}
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if (avcodec_open(CodecContext, Codec) < 0) {
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Free(false);
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_snprintf(ErrorMsg, MsgSize, "Could not open video codec");
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throw ErrorMsg;
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}
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// Always try to decode a frame to make sure all required parameters are known
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int64_t Dummy;
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if (DecodeNextFrame(DecodeFrame, &Dummy, ErrorMsg, MsgSize)) {
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Free(true);
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throw ErrorMsg;
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}
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VP.Width = CodecContext->width;
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VP.Height = CodecContext->height;;
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VP.FPSDenominator = 1;
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VP.FPSNumerator = 30;
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VP.NumFrames = Frames.size();
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VP.PixelFormat = CodecContext->pix_fmt;
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VP.FirstTime = ((Frames.front().DTS * Frames.TB.Num) / (double)Frames.TB.Den) / 1000;
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VP.LastTime = ((Frames.back().DTS * Frames.TB.Num) / (double)Frames.TB.Den) / 1000;
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if (VP.Width <= 0 || VP.Height <= 0) {
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Free(true);
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_snprintf(ErrorMsg, MsgSize, "Codec returned zero size video");
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throw ErrorMsg;
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}
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if (InitPP(PP, CodecContext->pix_fmt, ErrorMsg, MsgSize)) {
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Free(true);
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throw ErrorMsg;
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}
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// Calculate the average framerate
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if (Frames.size() >= 2) {
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double DTSDiff = (double)(Frames.back().DTS - Frames.front().DTS);
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VP.FPSDenominator = (unsigned int)(DTSDiff * mkv_TruncFloat(TI->TimecodeScale) / (double)1000 / (double)(VP.NumFrames - 1) + 0.5);
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VP.FPSNumerator = 1000000;
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}
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// Output the already decoded frame so it isn't wasted
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OutputFrame(DecodeFrame);
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LastFrameNum = 0;
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// Set AR variables
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VP.SARNum = TI->AV.Video.DisplayWidth * TI->AV.Video.PixelHeight;
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VP.SARDen = TI->AV.Video.DisplayHeight * TI->AV.Video.PixelWidth;
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// Set crop variables
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VP.CropLeft = TI->AV.Video.CropL;
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VP.CropRight = TI->AV.Video.CropR;
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VP.CropTop = TI->AV.Video.CropT;
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VP.CropBottom = TI->AV.Video.CropB;
|
|
}
|
|
|
|
MatroskaVideoSource::~MatroskaVideoSource() {
|
|
Free(true);
|
|
}
|
|
|
|
int MatroskaVideoSource::DecodeNextFrame(AVFrame *AFrame, int64_t *AFirstStartTime, char *ErrorMsg, unsigned MsgSize) {
|
|
int FrameFinished = 0;
|
|
*AFirstStartTime = -1;
|
|
|
|
ulonglong StartTime, EndTime, FilePos;
|
|
unsigned int Track, FrameFlags, FrameSize;
|
|
|
|
while (mkv_ReadFrame(MF, 0, &Track, &StartTime, &EndTime, &FilePos, &FrameSize, &FrameFlags) == 0) {
|
|
if (*AFirstStartTime < 0)
|
|
*AFirstStartTime = StartTime;
|
|
|
|
if (ReadFrame(FilePos, FrameSize, CS, MC, ErrorMsg, MsgSize))
|
|
return 1;
|
|
|
|
avcodec_decode_video(CodecContext, AFrame, &FrameFinished, MC.Buffer, FrameSize);
|
|
|
|
if (FrameFinished)
|
|
goto Done;
|
|
}
|
|
|
|
// Flush the last frames
|
|
if (CodecContext->has_b_frames)
|
|
avcodec_decode_video(CodecContext, AFrame, &FrameFinished, NULL, 0);
|
|
|
|
if (!FrameFinished)
|
|
goto Error;
|
|
|
|
Error:
|
|
Done:
|
|
return 0;
|
|
}
|
|
|
|
AVFrameLite *MatroskaVideoSource::GetFrame(int n, char *ErrorMsg, unsigned MsgSize) {
|
|
// PPFrame always holds frame LastFrameNum even if no PP is applied
|
|
if (LastFrameNum == n)
|
|
return OutputFrame(DecodeFrame);
|
|
|
|
bool HasSeeked = false;
|
|
|
|
if (n < CurrentFrame || Frames.FindClosestKeyFrame(n) > CurrentFrame) {
|
|
mkv_Seek(MF, Frames[n].DTS, MKVF_SEEK_TO_PREV_KEYFRAME);
|
|
avcodec_flush_buffers(CodecContext);
|
|
HasSeeked = true;
|
|
}
|
|
|
|
do {
|
|
int64_t StartTime;
|
|
if (DecodeNextFrame(DecodeFrame, &StartTime, ErrorMsg, MsgSize))
|
|
return NULL;
|
|
|
|
if (HasSeeked) {
|
|
HasSeeked = false;
|
|
|
|
if (StartTime < 0 || (CurrentFrame = Frames.FrameFromDTS(StartTime)) < 0) {
|
|
_snprintf(ErrorMsg, MsgSize, "Frame accurate seeking is not possible in this file");
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
CurrentFrame++;
|
|
} while (CurrentFrame <= n);
|
|
|
|
LastFrameNum = n;
|
|
return OutputFrame(DecodeFrame);
|
|
}
|