OpenShot Library | libopenshot 0.2.7
FFmpegWriter.h
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1/**
2 * @file
3 * @brief Header file for FFmpegWriter class
4 * @author Jonathan Thomas <jonathan@openshot.org>, Fabrice Bellard
5 *
6 * @ref License
7 */
8
9/* LICENSE
10 *
11 * Copyright (c) 2008-2019 OpenShot Studios, LLC, Fabrice Bellard
12 * (http://www.openshotstudios.com). This file is part of
13 * OpenShot Library (http://www.openshot.org), an open-source project
14 * dedicated to delivering high quality video editing and animation solutions
15 * to the world.
16 *
17 * This file is originally based on the Libavformat API example, and then modified
18 * by the libopenshot project.
19 *
20 * OpenShot Library is free software: you can redistribute it and/or modify
21 * it under the terms of the GNU General Public License as published by
22 * the Free Software Foundation, either version 3 of the License, or
23 * (at your option) any later version.
24 * * OpenShot Library (libopenshot) is free software: you can redistribute it
25 * and/or modify it under the terms of the GNU Lesser General Public License
26 * as published by the Free Software Foundation, either version 3 of the
27 * License, or (at your option) any later version.
28 *
29 * OpenShot Library (libopenshot) is distributed in the hope that it will be
30 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
31 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
32 * GNU Lesser General Public License for more details.
33 *
34 * You should have received a copy of the GNU Lesser General Public License
35 * along with OpenShot Library. If not, see <http://www.gnu.org/licenses/>.
36 */
37
38
39#ifndef OPENSHOT_FFMPEG_WRITER_H
40#define OPENSHOT_FFMPEG_WRITER_H
41
42#include "ReaderBase.h"
43#include "WriterBase.h"
44
45// Include FFmpeg headers and macros
46#include "FFmpegUtilities.h"
47
48#include <cmath>
49#include <ctime>
50#include <unistd.h>
51#include "CacheMemory.h"
52#include "OpenMPUtilities.h"
53#include "ZmqLogger.h"
54#include "Settings.h"
55
56
57namespace openshot {
58
59 /// This enumeration designates the type of stream when encoding (video or audio)
61 VIDEO_STREAM, ///< A video stream (used to determine which type of stream)
62 AUDIO_STREAM ///< An audio stream (used to determine which type of stream)
63 };
64
65 /**
66 * @brief This class uses the FFmpeg libraries, to write and encode video files and audio files.
67 *
68 * All FFmpeg options can be set using the SetOption() method, and any Reader may be used
69 * to generate openshot::Frame objects needed for writing. Be sure to use valid bit rates, frame
70 * rates, and sample rates (each format / codec has a limited # of valid options).
71 *
72 * @code SIMPLE EXAMPLE
73 *
74 * // Create a reader for a video
75 * openshot::FFmpegReader r("MyAwesomeVideo.webm");
76 * r.Open(); // Open the target reader
77 *
78 * // Create a writer (which will create a WebM video)
79 * openshot::FFmpegWriter w("/home/jonathan/NewVideo.webm");
80 *
81 * // Set options
82 *
83 * // Sample Rate: 44100, Channels: 2, Bitrate: 128000
84 * w.SetAudioOptions(true, "libvorbis", 44100, 2, openshot::ChannelLayout::LAYOUT_STEREO, 128000);
85 *
86 * // FPS: 24, Size: 720x480, Pixel Ratio: 1/1, Bitrate: 300000
87 * w.SetVideoOptions(true, "libvpx", openshot::Fraction(24,1), 720, 480, openshot::Fraction(1,1), false, false, 300000);
88 *
89 * // Open the writer
90 * w.Open();
91 *
92 * // Write all frames from the reader
93 * w.WriteFrame(&r, 1, r.info.video_length);
94 *
95 * // Close the reader & writer
96 * w.Close();
97 * r.Close();
98 * @endcode
99 *
100 * Here is a more advanced example, which sets some additional (and optional) encoding
101 * options.
102 *
103 * @code ADVANCED WRITER EXAMPLE
104 *
105 * // Create a reader for a video
106 * openshot::FFmpegReader r("MyAwesomeVideo.webm");
107 * r.Open(); // Open the reader
108 *
109 * // Create a writer (which will create a WebM video)
110 * openshot::FFmpegWriter w("/home/jonathan/NewVideo.webm");
111 *
112 * // Set options
113 *
114 * // Sample Rate: 44100, Channels: 2, Bitrate: 128000
115 * w.SetAudioOptions(true, "libvorbis", 44100, 2, openshot::ChannelLayout::LAYOUT_STEREO, 128000);
116 *
117 * // FPS: 24, Size: 720x480, Pixel Ratio: 1/1, Bitrate: 300000
118 * w.SetVideoOptions(true, "libvpx", openshot::Fraction(24,1), 720, 480, openshot::Fraction(1,1), false, false, 300000);
119 *
120 * // Prepare Streams (Optional method that must be called before any SetOption calls)
121 * w.PrepareStreams();
122 *
123 * // Set some specific encoding options (Optional methods)
124 * w.SetOption(VIDEO_STREAM, "qmin", "2" );
125 * w.SetOption(VIDEO_STREAM, "qmax", "30" );
126 * w.SetOption(VIDEO_STREAM, "crf", "10" );
127 * w.SetOption(VIDEO_STREAM, "rc_min_rate", "2000000" );
128 * w.SetOption(VIDEO_STREAM, "rc_max_rate", "4000000" );
129 * w.SetOption(VIDEO_STREAM, "max_b_frames", "10" );
130 *
131 * // Write the header of the video file
132 * w.WriteHeader();
133 *
134 * // Open the writer
135 * w.Open();
136 *
137 * // Write all frames from the reader
138 * w.WriteFrame(&r, 1, r.info.video_length);
139 *
140 * // Write the trailer of the video file
141 * w.WriteTrailer();
142 *
143 * // Close the reader & writer
144 * w.Close();
145 * r.Close();
146 * @endcode
147 */
148 class FFmpegWriter : public WriterBase {
149 private:
150 std::string path;
151 int cache_size;
152 bool is_writing;
153 bool is_open;
154 int64_t video_timestamp;
155 int64_t audio_timestamp;
156
157 bool prepare_streams;
158 bool write_header;
159 bool write_trailer;
160
161 AVOutputFormat *fmt;
162 AVFormatContext *oc;
163 AVStream *audio_st, *video_st;
164 AVCodecContext *video_codec_ctx;
165 AVCodecContext *audio_codec_ctx;
166 SwsContext *img_convert_ctx;
167 int16_t *samples;
168 uint8_t *audio_outbuf;
169 uint8_t *audio_encoder_buffer;
170
171 int num_of_rescalers;
172 int rescaler_position;
173 std::vector<SwsContext *> image_rescalers;
174
175 int audio_outbuf_size;
176 int audio_input_frame_size;
177 int initial_audio_input_frame_size;
178 int audio_input_position;
179 int audio_encoder_buffer_size;
180 SWRCONTEXT *avr;
181 SWRCONTEXT *avr_planar;
182
183 /* Resample options */
184 int original_sample_rate;
185 int original_channels;
186
187 std::shared_ptr<openshot::Frame> last_frame;
188 std::deque<std::shared_ptr<openshot::Frame> > spooled_audio_frames;
189 std::deque<std::shared_ptr<openshot::Frame> > spooled_video_frames;
190
191 std::deque<std::shared_ptr<openshot::Frame> > queued_audio_frames;
192 std::deque<std::shared_ptr<openshot::Frame> > queued_video_frames;
193
194 std::deque<std::shared_ptr<openshot::Frame> > processed_frames;
195 std::deque<std::shared_ptr<openshot::Frame> > deallocate_frames;
196
197 std::map<std::shared_ptr<openshot::Frame>, AVFrame *> av_frames;
198
199 /// Add an AVFrame to the cache
200 void add_avframe(std::shared_ptr<openshot::Frame> frame, AVFrame *av_frame);
201
202 /// Add an audio output stream
203 AVStream *add_audio_stream();
204
205 /// Add a video output stream
206 AVStream *add_video_stream();
207
208 /// Allocate an AVFrame object
209 AVFrame *allocate_avframe(PixelFormat pix_fmt, int width, int height, int *buffer_size, uint8_t *new_buffer);
210
211 /// Auto detect format (from path)
212 void auto_detect_format();
213
214 /// Close the audio codec
215 void close_audio(AVFormatContext *oc, AVStream *st);
216
217 /// Close the video codec
218 void close_video(AVFormatContext *oc, AVStream *st);
219
220 /// Flush encoders
221 void flush_encoders();
222
223 /// initialize streams
224 void initialize_streams();
225
226 /// @brief Init a collection of software rescalers (thread safe)
227 /// @param source_width The source width of the image scalers (used to cache a bunch of scalers)
228 /// @param source_height The source height of the image scalers (used to cache a bunch of scalers)
229 void InitScalers(int source_width, int source_height);
230
231 /// open audio codec
232 void open_audio(AVFormatContext *oc, AVStream *st);
233
234 /// open video codec
235 void open_video(AVFormatContext *oc, AVStream *st);
236
237 /// process video frame
238 void process_video_packet(std::shared_ptr<openshot::Frame> frame);
239
240 /// write all queued frames' audio to the video file
241 void write_audio_packets(bool is_final);
242
243 /// write video frame
244 bool write_video_packet(std::shared_ptr<openshot::Frame> frame, AVFrame *frame_final);
245
246 /// write all queued frames
247 void write_queued_frames();
248
249 public:
250
251 /// @brief Constructor for FFmpegWriter.
252 /// Throws an exception on failure to open path.
253 ///
254 /// @param path The file path of the video file you want to open and read
255 FFmpegWriter(const std::string& path);
256
257 /// Close the writer
258 void Close();
259
260 /// Get the cache size (number of frames to queue before writing)
261 int GetCacheSize() { return cache_size; };
262
263 /// Determine if writer is open or closed
264 bool IsOpen() { return is_open; };
265
266 /// Determine if codec name is valid
267 static bool IsValidCodec(std::string codec_name);
268
269 /// Open writer
270 void Open();
271
272 /// Output the ffmpeg info about this format, streams, and codecs (i.e. dump format)
273 void OutputStreamInfo();
274
275 /// @brief Prepare & initialize streams and open codecs. This method is called automatically
276 /// by the Open() method if this method has not yet been called.
277 void PrepareStreams();
278
279 /// Remove & deallocate all software scalers
280 void RemoveScalers();
281
282 /// @brief Set audio resample options
283 /// @param sample_rate The number of samples per second of the audio
284 /// @param channels The number of audio channels
285 void ResampleAudio(int sample_rate, int channels);
286
287 /// @brief Set audio export options
288 /// @param has_audio Does this file need an audio stream?
289 /// @param codec The codec used to encode the audio for this file
290 /// @param sample_rate The number of audio samples needed in this file
291 /// @param channels The number of audio channels needed in this file
292 /// @param channel_layout The 'layout' of audio channels (i.e. mono, stereo, surround, etc...)
293 /// @param bit_rate The audio bit rate used during encoding
294 ///
295 /// \note This is an overloaded function.
296 void SetAudioOptions(bool has_audio, std::string codec, int sample_rate, int channels, openshot::ChannelLayout channel_layout, int bit_rate);
297
298 /// @brief Set audio export options.
299 ///
300 /// Enables the stream and configures a default 2-channel stereo layout.
301 ///
302 /// @param codec The codec used to encode the audio for this file
303 /// @param sample_rate The number of audio samples needed in this file
304 /// @param bit_rate The audio bit rate used during encoding
305 ///
306 /// \note This is an overloaded function.
307 void SetAudioOptions(std::string codec, int sample_rate, int bit_rate);
308
309 /// @brief Set the cache size
310 /// @param new_size The number of frames to queue before writing to the file
311 void SetCacheSize(int new_size) { cache_size = new_size; };
312
313 /// @brief Set video export options
314 /// @param has_video Does this file need a video stream
315 /// @param codec The codec used to encode the images in this video
316 /// @param fps The number of frames per second
317 /// @param width The width in pixels of this video
318 /// @param height The height in pixels of this video
319 /// @param pixel_ratio The shape of the pixels represented as a openshot::Fraction (1x1 is most common / square pixels)
320 /// @param interlaced Does this video need to be interlaced?
321 /// @param top_field_first Which frame should be used as the top field?
322 /// @param bit_rate The video bit rate used during encoding
323 ///
324 /// \note This is an overloaded function.
325 void SetVideoOptions(bool has_video, std::string codec, openshot::Fraction fps, int width, int height, openshot::Fraction pixel_ratio, bool interlaced, bool top_field_first, int bit_rate);
326
327 /// @brief Set video export options.
328 ///
329 /// Enables the stream and configures non-interlaced video with a 1:1 pixel aspect ratio.
330 ///
331 /// @param codec The codec used to encode the images in this video
332 /// @param width The width in pixels of this video
333 /// @param height The height in pixels of this video
334 /// @param fps The number of frames per second
335 /// @param bit_rate The video bit rate used during encoding
336 ///
337 /// \note This is an overloaded function.
338 /// \warning Observe the argument order, which is consistent with the openshot::Timeline constructor, but differs from the other signature.
339 void SetVideoOptions(std::string codec, int width, int height, openshot::Fraction fps, int bit_rate);
340
341 /// @brief Set custom options (some codecs accept additional params). This must be called after the
342 /// PrepareStreams() method, otherwise the streams have not been initialized yet.
343 ///
344 /// @param stream The stream (openshot::StreamType) this option should apply to
345 /// @param name The name of the option you want to set (i.e. qmin, qmax, etc...)
346 /// @param value The new value of this option
347 void SetOption(openshot::StreamType stream, std::string name, std::string value);
348
349 /// @brief Write the file header (after the options are set). This method is called automatically
350 /// by the Open() method if this method has not yet been called.
351 void WriteHeader();
352
353 /// @brief Add a frame to the stack waiting to be encoded.
354 /// @param frame The openshot::Frame object to write to this image
355 ///
356 /// \note This is an overloaded function.
357 void WriteFrame(std::shared_ptr<openshot::Frame> frame);
358
359 /// @brief Write a block of frames from a reader
360 /// @param reader A openshot::ReaderBase object which will provide frames to be written
361 /// @param start The starting frame number of the reader
362 /// @param length The number of frames to write
363 ///
364 /// \note This is an overloaded function.
365 void WriteFrame(openshot::ReaderBase *reader, int64_t start, int64_t length);
366
367 /// @brief Write the file trailer (after all frames are written). This is called automatically
368 /// by the Close() method if this method has not yet been called.
369 void WriteTrailer();
370
371 };
372
373}
374
375#endif
Header file for CacheMemory class.
Header file for FFmpegUtilities.
#define PixelFormat
#define SWRCONTEXT
Header file for OpenMPUtilities (set some common macros)
Header file for ReaderBase class.
Header file for global Settings class.
Header file for WriterBase class.
Header file for ZeroMQ-based Logger class.
This class uses the FFmpeg libraries, to write and encode video files and audio files.
Definition: FFmpegWriter.h:148
void Close()
Close the writer.
void SetAudioOptions(bool has_audio, std::string codec, int sample_rate, int channels, openshot::ChannelLayout channel_layout, int bit_rate)
Set audio export options.
void SetOption(openshot::StreamType stream, std::string name, std::string value)
Set custom options (some codecs accept additional params). This must be called after the PrepareStrea...
void PrepareStreams()
Prepare & initialize streams and open codecs. This method is called automatically by the Open() metho...
void SetVideoOptions(bool has_video, std::string codec, openshot::Fraction fps, int width, int height, openshot::Fraction pixel_ratio, bool interlaced, bool top_field_first, int bit_rate)
Set video export options.
bool IsOpen()
Determine if writer is open or closed.
Definition: FFmpegWriter.h:264
void SetCacheSize(int new_size)
Set the cache size.
Definition: FFmpegWriter.h:311
void ResampleAudio(int sample_rate, int channels)
Set audio resample options.
int GetCacheSize()
Get the cache size (number of frames to queue before writing)
Definition: FFmpegWriter.h:261
void Open()
Open writer.
void WriteHeader()
Write the file header (after the options are set). This method is called automatically by the Open() ...
FFmpegWriter(const std::string &path)
Constructor for FFmpegWriter. Throws an exception on failure to open path.
static bool IsValidCodec(std::string codec_name)
Determine if codec name is valid.
void OutputStreamInfo()
Output the ffmpeg info about this format, streams, and codecs (i.e. dump format)
void WriteFrame(std::shared_ptr< openshot::Frame > frame)
Add a frame to the stack waiting to be encoded.
void WriteTrailer()
Write the file trailer (after all frames are written). This is called automatically by the Close() me...
void RemoveScalers()
Remove & deallocate all software scalers.
This class represents a fraction.
Definition: Fraction.h:48
This abstract class is the base class, used by all readers in libopenshot.
Definition: ReaderBase.h:98
This abstract class is the base class, used by writers. Writers are types of classes that encode vide...
Definition: WriterBase.h:88
This namespace is the default namespace for all code in the openshot library.
Definition: Compressor.h:47
ChannelLayout
This enumeration determines the audio channel layout (such as stereo, mono, 5 point surround,...
StreamType
This enumeration designates the type of stream when encoding (video or audio)
Definition: FFmpegWriter.h:60
@ AUDIO_STREAM
An audio stream (used to determine which type of stream)
Definition: FFmpegWriter.h:62
@ VIDEO_STREAM
A video stream (used to determine which type of stream)
Definition: FFmpegWriter.h:61