src/platform/ffmpeg/ffmpeg-encoder.c (view raw)
1/* Copyright (c) 2013-2014 Jeffrey Pfau
2 *
3 * This Source Code Form is subject to the terms of the Mozilla Public
4 * License, v. 2.0. If a copy of the MPL was not distributed with this
5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6#include "ffmpeg-encoder.h"
7
8#include "gba-video.h"
9
10#include <libavcodec/avcodec.h>
11
12#include <libavutil/imgutils.h>
13#include <libavutil/opt.h>
14
15#include <libavresample/avresample.h>
16#include <libswscale/swscale.h>
17
18static void _ffmpegPostVideoFrame(struct GBAAVStream*, struct GBAVideoRenderer* renderer);
19static void _ffmpegPostAudioFrame(struct GBAAVStream*, int32_t left, int32_t right);
20
21enum {
22 PREFERRED_SAMPLE_RATE = 0x8000
23};
24
25void FFmpegEncoderInit(struct FFmpegEncoder* encoder) {
26 av_register_all();
27
28 encoder->d.postVideoFrame = _ffmpegPostVideoFrame;
29 encoder->d.postAudioFrame = _ffmpegPostAudioFrame;
30
31 encoder->audioCodec = 0;
32 encoder->videoCodec = 0;
33 encoder->containerFormat = 0;
34 FFmpegEncoderSetAudio(encoder, "flac", 0);
35 FFmpegEncoderSetVideo(encoder, "png", 0);
36 FFmpegEncoderSetContainer(encoder, "matroska");
37 FFmpegEncoderSetDimensions(encoder, VIDEO_HORIZONTAL_PIXELS, VIDEO_VERTICAL_PIXELS);
38 encoder->resampleContext = 0;
39 encoder->absf = 0;
40 encoder->context = 0;
41}
42
43bool FFmpegEncoderSetAudio(struct FFmpegEncoder* encoder, const char* acodec, unsigned abr) {
44 static const struct {
45 int format;
46 int priority;
47 } priorities[] = {
48 { AV_SAMPLE_FMT_S16, 0 },
49 { AV_SAMPLE_FMT_S16P, 1 },
50 { AV_SAMPLE_FMT_S32, 2 },
51 { AV_SAMPLE_FMT_S32P, 2 },
52 { AV_SAMPLE_FMT_FLT, 3 },
53 { AV_SAMPLE_FMT_FLTP, 3 },
54 { AV_SAMPLE_FMT_DBL, 4 },
55 { AV_SAMPLE_FMT_DBLP, 4 }
56 };
57
58 if (!acodec) {
59 encoder->audioCodec = 0;
60 return true;
61 }
62
63 AVCodec* codec = avcodec_find_encoder_by_name(acodec);
64 if (!codec) {
65 return false;
66 }
67
68 if (!codec->sample_fmts) {
69 return false;
70 }
71 size_t i;
72 size_t j;
73 int priority = INT_MAX;
74 encoder->sampleFormat = AV_SAMPLE_FMT_NONE;
75 for (i = 0; codec->sample_fmts[i] != AV_SAMPLE_FMT_NONE; ++i) {
76 for (j = 0; j < sizeof(priorities) / sizeof(*priorities); ++j) {
77 if (codec->sample_fmts[i] == priorities[j].format && priority > priorities[j].priority) {
78 priority = priorities[j].priority;
79 encoder->sampleFormat = codec->sample_fmts[i];
80 }
81 }
82 }
83 if (encoder->sampleFormat == AV_SAMPLE_FMT_NONE) {
84 return false;
85 }
86 encoder->sampleRate = PREFERRED_SAMPLE_RATE;
87 if (codec->supported_samplerates) {
88 for (i = 0; codec->supported_samplerates[i]; ++i) {
89 if (codec->supported_samplerates[i] < PREFERRED_SAMPLE_RATE) {
90 continue;
91 }
92 if (encoder->sampleRate == PREFERRED_SAMPLE_RATE || encoder->sampleRate > codec->supported_samplerates[i]) {
93 encoder->sampleRate = codec->supported_samplerates[i];
94 }
95 }
96 } else if (codec->id == AV_CODEC_ID_AAC) {
97 // HACK: AAC doesn't support 32768Hz (it rounds to 32000), but libfaac doesn't tell us that
98 encoder->sampleRate = 44100;
99 }
100 encoder->audioCodec = acodec;
101 encoder->audioBitrate = abr;
102 return true;
103}
104
105bool FFmpegEncoderSetVideo(struct FFmpegEncoder* encoder, const char* vcodec, unsigned vbr) {
106 static const struct {
107 enum AVPixelFormat format;
108 int priority;
109 } priorities[] = {
110 { AV_PIX_FMT_RGB555, 0 },
111 { AV_PIX_FMT_BGR555, 0 },
112 { AV_PIX_FMT_RGB565, 1 },
113 { AV_PIX_FMT_BGR565, 1 },
114 { AV_PIX_FMT_RGB24, 2 },
115 { AV_PIX_FMT_BGR24, 2 },
116 { AV_PIX_FMT_BGR0, 3 },
117 { AV_PIX_FMT_RGB0, 3 },
118 { AV_PIX_FMT_0BGR, 3 },
119 { AV_PIX_FMT_0RGB, 3 },
120 { AV_PIX_FMT_RGB8, 3 },
121 { AV_PIX_FMT_BGR8, 3 },
122 { AV_PIX_FMT_YUV422P, 4 },
123 { AV_PIX_FMT_YUV444P, 5 },
124 { AV_PIX_FMT_YUV420P, 6 }
125 };
126 AVCodec* codec = avcodec_find_encoder_by_name(vcodec);
127 if (!codec) {
128 return false;
129 }
130
131 size_t i;
132 size_t j;
133 int priority = INT_MAX;
134 encoder->pixFormat = AV_PIX_FMT_NONE;
135 for (i = 0; codec->pix_fmts[i] != AV_PIX_FMT_NONE; ++i) {
136 for (j = 0; j < sizeof(priorities) / sizeof(*priorities); ++j) {
137 if (codec->pix_fmts[i] == priorities[j].format && priority > priorities[j].priority) {
138 priority = priorities[j].priority;
139 encoder->pixFormat = codec->pix_fmts[i];
140 }
141 }
142 }
143 if (encoder->pixFormat == AV_PIX_FMT_NONE) {
144 return false;
145 }
146 encoder->videoCodec = vcodec;
147 encoder->videoBitrate = vbr;
148 return true;
149}
150
151bool FFmpegEncoderSetContainer(struct FFmpegEncoder* encoder, const char* container) {
152 AVOutputFormat* oformat = av_guess_format(container, 0, 0);
153 if (!oformat) {
154 return false;
155 }
156 encoder->containerFormat = container;
157 return true;
158}
159
160void FFmpegEncoderSetDimensions(struct FFmpegEncoder* encoder, int width, int height) {
161 encoder->width = width > 0 ? width : VIDEO_HORIZONTAL_PIXELS;
162 encoder->height = height > 0 ? height : VIDEO_VERTICAL_PIXELS;
163}
164
165bool FFmpegEncoderVerifyContainer(struct FFmpegEncoder* encoder) {
166 AVOutputFormat* oformat = av_guess_format(encoder->containerFormat, 0, 0);
167 AVCodec* acodec = avcodec_find_encoder_by_name(encoder->audioCodec);
168 AVCodec* vcodec = avcodec_find_encoder_by_name(encoder->videoCodec);
169 if ((encoder->audioCodec && !acodec) || !vcodec || !oformat) {
170 return false;
171 }
172 if (encoder->audioCodec && !avformat_query_codec(oformat, acodec->id, FF_COMPLIANCE_EXPERIMENTAL)) {
173 return false;
174 }
175 if (!avformat_query_codec(oformat, vcodec->id, FF_COMPLIANCE_EXPERIMENTAL)) {
176 return false;
177 }
178 return true;
179}
180
181bool FFmpegEncoderOpen(struct FFmpegEncoder* encoder, const char* outfile) {
182 AVCodec* acodec = avcodec_find_encoder_by_name(encoder->audioCodec);
183 AVCodec* vcodec = avcodec_find_encoder_by_name(encoder->videoCodec);
184 if ((encoder->audioCodec && !acodec) || !vcodec || !FFmpegEncoderVerifyContainer(encoder)) {
185 return false;
186 }
187
188 encoder->currentAudioSample = 0;
189 encoder->currentAudioFrame = 0;
190 encoder->currentVideoFrame = 0;
191 encoder->nextAudioPts = 0;
192
193 avformat_alloc_output_context2(&encoder->context, 0, 0, outfile);
194
195 encoder->context->oformat = av_guess_format(encoder->containerFormat, 0, 0);
196
197 if (acodec) {
198 encoder->audioStream = avformat_new_stream(encoder->context, acodec);
199 encoder->audio = encoder->audioStream->codec;
200 encoder->audio->bit_rate = encoder->audioBitrate;
201 encoder->audio->channels = 2;
202 encoder->audio->channel_layout = AV_CH_LAYOUT_STEREO;
203 encoder->audio->sample_rate = encoder->sampleRate;
204 encoder->audio->sample_fmt = encoder->sampleFormat;
205 AVDictionary* opts = 0;
206 av_dict_set(&opts, "strict", "-2", 0);
207 if (encoder->context->oformat->flags & AVFMT_GLOBALHEADER) {
208 encoder->audio->flags |= CODEC_FLAG_GLOBAL_HEADER;
209 }
210 avcodec_open2(encoder->audio, acodec, &opts);
211 av_dict_free(&opts);
212 encoder->audioFrame = av_frame_alloc();
213 encoder->audioFrame->nb_samples = encoder->audio->frame_size;
214 encoder->audioFrame->format = encoder->audio->sample_fmt;
215 encoder->audioFrame->pts = 0;
216 encoder->resampleContext = avresample_alloc_context();
217 av_opt_set_int(encoder->resampleContext, "in_channel_layout", AV_CH_LAYOUT_STEREO, 0);
218 av_opt_set_int(encoder->resampleContext, "out_channel_layout", AV_CH_LAYOUT_STEREO, 0);
219 av_opt_set_int(encoder->resampleContext, "in_sample_rate", PREFERRED_SAMPLE_RATE, 0);
220 av_opt_set_int(encoder->resampleContext, "out_sample_rate", encoder->sampleRate, 0);
221 av_opt_set_int(encoder->resampleContext, "in_sample_fmt", AV_SAMPLE_FMT_S16, 0);
222 av_opt_set_int(encoder->resampleContext, "out_sample_fmt", encoder->sampleFormat, 0);
223 avresample_open(encoder->resampleContext);
224 encoder->audioBufferSize = (encoder->audioFrame->nb_samples * PREFERRED_SAMPLE_RATE / encoder->sampleRate) * 4;
225 encoder->audioBuffer = av_malloc(encoder->audioBufferSize);
226 encoder->postaudioBufferSize = av_samples_get_buffer_size(0, encoder->audio->channels, encoder->audio->frame_size, encoder->audio->sample_fmt, 0);
227 encoder->postaudioBuffer = av_malloc(encoder->postaudioBufferSize);
228 avcodec_fill_audio_frame(encoder->audioFrame, encoder->audio->channels, encoder->audio->sample_fmt, (const uint8_t*) encoder->postaudioBuffer, encoder->postaudioBufferSize, 0);
229
230 if (encoder->audio->codec->id == AV_CODEC_ID_AAC &&
231 (strcasecmp(encoder->containerFormat, "mp4") ||
232 strcasecmp(encoder->containerFormat, "m4v") ||
233 strcasecmp(encoder->containerFormat, "mov"))) {
234 // MP4 container doesn't support the raw ADTS AAC format that the encoder spits out
235 encoder->absf = av_bitstream_filter_init("aac_adtstoasc");
236 }
237 }
238
239 encoder->videoStream = avformat_new_stream(encoder->context, vcodec);
240 encoder->video = encoder->videoStream->codec;
241 encoder->video->bit_rate = encoder->videoBitrate;
242 encoder->video->width = encoder->width;
243 encoder->video->height = encoder->height;
244 encoder->video->time_base = (AVRational) { VIDEO_TOTAL_LENGTH, GBA_ARM7TDMI_FREQUENCY };
245 encoder->video->pix_fmt = encoder->pixFormat;
246 encoder->video->gop_size = 60;
247 encoder->video->max_b_frames = 3;
248 if (encoder->context->oformat->flags & AVFMT_GLOBALHEADER) {
249 encoder->video->flags |= CODEC_FLAG_GLOBAL_HEADER;
250 }
251 if (strcmp(vcodec->name, "libx264") == 0) {
252 // Try to adaptively figure out when you can use a slower encoder
253 if (encoder->width * encoder->height > 1000000) {
254 av_opt_set(encoder->video->priv_data, "preset", "superfast", 0);
255 } else if (encoder->width * encoder->height > 500000) {
256 av_opt_set(encoder->video->priv_data, "preset", "veryfast", 0);
257 } else {
258 av_opt_set(encoder->video->priv_data, "preset", "faster", 0);
259 }
260 av_opt_set(encoder->video->priv_data, "tune", "zerolatency", 0);
261 }
262 avcodec_open2(encoder->video, vcodec, 0);
263 encoder->videoFrame = av_frame_alloc();
264 encoder->videoFrame->format = encoder->video->pix_fmt;
265 encoder->videoFrame->width = encoder->video->width;
266 encoder->videoFrame->height = encoder->video->height;
267 encoder->videoFrame->pts = 0;
268 encoder->scaleContext = sws_getContext(VIDEO_HORIZONTAL_PIXELS, VIDEO_VERTICAL_PIXELS, AV_PIX_FMT_0BGR32,
269 encoder->videoFrame->width, encoder->videoFrame->height, encoder->video->pix_fmt,
270 SWS_POINT, 0, 0, 0);
271 av_image_alloc(encoder->videoFrame->data, encoder->videoFrame->linesize, encoder->video->width, encoder->video->height, encoder->video->pix_fmt, 32);
272
273 avio_open(&encoder->context->pb, outfile, AVIO_FLAG_WRITE);
274 avformat_write_header(encoder->context, 0);
275
276 return true;
277}
278
279void FFmpegEncoderClose(struct FFmpegEncoder* encoder) {
280 if (!encoder->context) {
281 return;
282 }
283 av_write_trailer(encoder->context);
284 avio_close(encoder->context->pb);
285
286 if (encoder->audioCodec) {
287 av_free(encoder->postaudioBuffer);
288 if (encoder->audioBuffer) {
289 av_free(encoder->audioBuffer);
290 }
291 av_frame_free(&encoder->audioFrame);
292 avcodec_close(encoder->audio);
293
294 if (encoder->resampleContext) {
295 avresample_close(encoder->resampleContext);
296 }
297
298 if (encoder->absf) {
299 av_bitstream_filter_close(encoder->absf);
300 encoder->absf = 0;
301 }
302 }
303
304 av_frame_free(&encoder->videoFrame);
305 avcodec_close(encoder->video);
306
307 sws_freeContext(encoder->scaleContext);
308
309 avformat_free_context(encoder->context);
310 encoder->context = 0;
311}
312
313bool FFmpegEncoderIsOpen(struct FFmpegEncoder* encoder) {
314 return !!encoder->context;
315}
316
317void _ffmpegPostAudioFrame(struct GBAAVStream* stream, int32_t left, int32_t right) {
318 struct FFmpegEncoder* encoder = (struct FFmpegEncoder*) stream;
319 if (!encoder->context || !encoder->audioCodec) {
320 return;
321 }
322
323 av_frame_make_writable(encoder->audioFrame);
324 encoder->audioBuffer[encoder->currentAudioSample * 2] = left;
325 encoder->audioBuffer[encoder->currentAudioSample * 2 + 1] = right;
326
327 ++encoder->currentAudioFrame;
328 ++encoder->currentAudioSample;
329
330 if ((encoder->currentAudioSample * 4) < encoder->audioBufferSize) {
331 return;
332 }
333 encoder->currentAudioSample = 0;
334
335 int channelSize = 2 * av_get_bytes_per_sample(encoder->audio->sample_fmt);
336 avresample_convert(encoder->resampleContext,
337 0, 0, encoder->postaudioBufferSize / channelSize,
338 (uint8_t**) &encoder->audioBuffer, 0, encoder->audioBufferSize / 4);
339 if ((ssize_t) avresample_available(encoder->resampleContext) < (ssize_t) encoder->postaudioBufferSize / channelSize) {
340 return;
341 }
342 avresample_read(encoder->resampleContext, encoder->audioFrame->data, encoder->postaudioBufferSize / channelSize);
343
344 AVRational timeBase = { 1, PREFERRED_SAMPLE_RATE };
345 encoder->audioFrame->pts = encoder->nextAudioPts;
346 encoder->nextAudioPts = av_rescale_q(encoder->currentAudioFrame, timeBase, encoder->audioStream->time_base);
347
348 AVPacket packet;
349 av_init_packet(&packet);
350 packet.data = 0;
351 packet.size = 0;
352 int gotData;
353 avcodec_encode_audio2(encoder->audio, &packet, encoder->audioFrame, &gotData);
354 if (gotData) {
355 if (encoder->absf) {
356 AVPacket tempPacket = packet;
357 int success = av_bitstream_filter_filter(encoder->absf, encoder->audio, 0,
358 &tempPacket.data, &tempPacket.size,
359 packet.data, packet.size, 0);
360 if (success > 0) {
361 tempPacket.buf = av_buffer_create(tempPacket.data, tempPacket.size, av_buffer_default_free, 0, 0);
362 av_free_packet(&packet);
363 }
364 packet = tempPacket;
365 }
366 packet.stream_index = encoder->audioStream->index;
367 av_interleaved_write_frame(encoder->context, &packet);
368 }
369 av_free_packet(&packet);
370}
371
372void _ffmpegPostVideoFrame(struct GBAAVStream* stream, struct GBAVideoRenderer* renderer) {
373 struct FFmpegEncoder* encoder = (struct FFmpegEncoder*) stream;
374 if (!encoder->context) {
375 return;
376 }
377 uint8_t* pixels;
378 unsigned stride;
379 renderer->getPixels(renderer, &stride, (void**) &pixels);
380 stride *= 4;
381
382 AVPacket packet;
383
384 av_init_packet(&packet);
385 packet.data = 0;
386 packet.size = 0;
387 av_frame_make_writable(encoder->videoFrame);
388 encoder->videoFrame->pts = av_rescale_q(encoder->currentVideoFrame, encoder->video->time_base, encoder->videoStream->time_base);
389 ++encoder->currentVideoFrame;
390
391 sws_scale(encoder->scaleContext, (const uint8_t* const*) &pixels, (const int*) &stride, 0, VIDEO_VERTICAL_PIXELS, encoder->videoFrame->data, encoder->videoFrame->linesize);
392
393 int gotData;
394 avcodec_encode_video2(encoder->video, &packet, encoder->videoFrame, &gotData);
395 if (gotData) {
396 if (encoder->videoStream->codec->coded_frame->key_frame) {
397 packet.flags |= AV_PKT_FLAG_KEY;
398 }
399 packet.stream_index = encoder->videoStream->index;
400 av_interleaved_write_frame(encoder->context, &packet);
401 }
402 av_free_packet(&packet);
403}