1 /*
2  * Copyright (C) 2019 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include <source/FrameBufferSource.h>
18 
19 #include <algorithm>
20 #include <chrono>
21 
22 #include <libyuv/convert.h>
23 
24 #include "host/libs/config/cuttlefish_config.h"
25 
26 #include "vpx/vpx_encoder.h"
27 #include "vpx/vpx_codec.h"
28 #include "vpx/vp8cx.h"
29 
30 #include <gflags/gflags.h>
31 
32 #define ENABLE_LOGGING          0
33 
34 namespace android {
35 
36 namespace {
GetNowUs()37     int64_t GetNowUs() {
38         auto now = std::chrono::steady_clock::now().time_since_epoch();
39         return std::chrono::duration_cast<std::chrono::microseconds>(now).count();
40     }
41 }
42 
43 struct FrameBufferSource::Encoder {
44     Encoder() = default;
45     virtual ~Encoder() = default;
46 
47     virtual void forceIDRFrame() = 0;
48     virtual bool isForcingIDRFrame() const = 0;
49 
50     virtual void storeFrame(const void* frame) = 0;
51     virtual std::shared_ptr<SBuffer> encodeStoredFrame(int64_t timeUs) = 0;
52 };
53 
54 ////////////////////////////////////////////////////////////////////////////////
55 
56 struct FrameBufferSource::VPXEncoder : public FrameBufferSource::Encoder {
57     VPXEncoder(int width, int height, int rateHz);
58     ~VPXEncoder() override;
59 
60     void forceIDRFrame() override;
61     bool isForcingIDRFrame() const override;
62 
63     void storeFrame(const void* frame) override;
64     std::shared_ptr<SBuffer> encodeStoredFrame(int64_t timeUs) override;
65 
66 private:
67     int mWidth, mHeight, mRefreshRateHz;
68 
69     int mSizeY, mSizeUV;
70     void *mI420Data;
71 
72     vpx_codec_iface_t *mCodecInterface;
73     std::unique_ptr<vpx_codec_enc_cfg_t> mCodecConfiguration;
74 
75     using contextFreeFunc = std::function<vpx_codec_err_t(vpx_codec_ctx_t *)>;
76     std::unique_ptr<vpx_codec_ctx_t, contextFreeFunc> mCodecContext;
77 
78     std::atomic<bool> mForceIDRFrame;
79     bool mFirstFrame;
80     bool mStoredFrame;
81     int64_t mLastTimeUs;
82 };
83 
GetCPUCoreCount()84 static int GetCPUCoreCount() {
85     int cpuCoreCount;
86 
87 #if defined(_SC_NPROCESSORS_ONLN)
88     cpuCoreCount = sysconf(_SC_NPROCESSORS_ONLN);
89 #else
90     // _SC_NPROC_ONLN must be defined...
91     cpuCoreCount = sysconf(_SC_NPROC_ONLN);
92 #endif
93 
94     CHECK_GE(cpuCoreCount, 1);
95     return cpuCoreCount;
96 }
97 
VPXEncoder(int width,int height,int rateHz)98 FrameBufferSource::VPXEncoder::VPXEncoder(int width, int height, int rateHz)
99     : mWidth(width),
100       mHeight(height),
101       mRefreshRateHz(rateHz),
102       mCodecContext(nullptr, vpx_codec_destroy),
103       mForceIDRFrame(false),
104       mFirstFrame(true),
105       mStoredFrame(false),
106       mLastTimeUs(0) {
107 
108     CHECK((width & 1) == 0);
109     CHECK((height & 1) == 0);
110     mSizeY = width * height;
111     mSizeUV = (width / 2) * (height / 2);
112     size_t totalSize = mSizeY + 2 * mSizeUV;
113     mI420Data = malloc(totalSize);
114 
115     mCodecInterface = vpx_codec_vp8_cx();
116     mCodecConfiguration = std::make_unique<vpx_codec_enc_cfg_t>();
117 
118     auto res = vpx_codec_enc_config_default(
119             mCodecInterface, mCodecConfiguration.get(), 0 /* usage */);
120 
121     mCodecConfiguration->g_w = width;
122     mCodecConfiguration->g_h = height;
123     mCodecConfiguration->g_threads = std::min(GetCPUCoreCount(), 64);
124     mCodecConfiguration->g_error_resilient = false;
125     mCodecConfiguration->g_timebase.num = 1;
126     mCodecConfiguration->g_timebase.den = 1000000;
127     mCodecConfiguration->rc_target_bitrate = 2500;  // This appears to match x264
128     mCodecConfiguration->rc_end_usage = VPX_VBR;
129     mCodecConfiguration->rc_dropframe_thresh = 0;
130     mCodecConfiguration->g_lag_in_frames = 0;
131 
132     mCodecConfiguration->g_profile = 0;
133 
134     CHECK_EQ(res, VPX_CODEC_OK);
135 
136     mCodecContext.reset(new vpx_codec_ctx_t);
137 
138     res = vpx_codec_enc_init(
139             mCodecContext.get(),
140             mCodecInterface,
141             mCodecConfiguration.get(),
142             0 /* flags */);
143 
144     CHECK_EQ(res, VPX_CODEC_OK);
145 
146     res = vpx_codec_control(mCodecContext.get(), VP8E_SET_TOKEN_PARTITIONS, 0);
147     CHECK_EQ(res, VPX_CODEC_OK);
148 }
149 
~VPXEncoder()150 FrameBufferSource::VPXEncoder::~VPXEncoder() {
151     free(mI420Data);
152     mI420Data = nullptr;
153 }
154 
forceIDRFrame()155 void FrameBufferSource::VPXEncoder::forceIDRFrame() {
156     mForceIDRFrame = true;
157 }
158 
isForcingIDRFrame() const159 bool FrameBufferSource::VPXEncoder::isForcingIDRFrame() const {
160     return mForceIDRFrame;
161 }
162 
storeFrame(const void * frame)163 void FrameBufferSource::VPXEncoder::storeFrame(const void *frame) {
164     uint8_t *yPlane = static_cast<uint8_t *>(mI420Data);
165     uint8_t *uPlane = yPlane + mSizeY;
166     uint8_t *vPlane = uPlane + mSizeUV;
167 
168     libyuv::ABGRToI420(
169             static_cast<const uint8_t *>(frame),
170             mWidth * 4,
171             yPlane,
172             mWidth,
173             uPlane,
174             mWidth / 2,
175             vPlane,
176             mWidth / 2,
177             mWidth,
178             mHeight);
179     mStoredFrame = true;
180 }
181 
encodeStoredFrame(int64_t timeUs)182 std::shared_ptr<SBuffer> FrameBufferSource::VPXEncoder::encodeStoredFrame(
183         int64_t timeUs) {
184     if (!mStoredFrame) {
185         return nullptr;
186     }
187     vpx_image_t raw_frame;
188     vpx_img_wrap(&raw_frame, VPX_IMG_FMT_I420, mWidth, mHeight,
189                  2 /* stride_align */,
190                  reinterpret_cast<unsigned char *>(mI420Data));
191 
192     vpx_enc_frame_flags_t flags = 0;
193 
194     if (mForceIDRFrame.exchange(false)) {
195         flags |= VPX_EFLAG_FORCE_KF;
196     }
197 
198     uint32_t frameDuration;
199 
200     if (!mFirstFrame) {
201         frameDuration = timeUs - mLastTimeUs;
202     } else {
203         frameDuration = 1000000 / mRefreshRateHz;
204         mFirstFrame = false;
205     }
206 
207     mLastTimeUs = timeUs;
208 
209     auto res = vpx_codec_encode(
210             mCodecContext.get(),
211             &raw_frame,
212             timeUs,
213             frameDuration,
214             flags,
215             VPX_DL_REALTIME);
216 
217     if (res != VPX_CODEC_OK) {
218         LOG(ERROR) << "vpx_codec_encode failed w/ " << res;
219         return nullptr;
220     }
221 
222     vpx_codec_iter_t iter = nullptr;
223     const vpx_codec_cx_pkt_t *packet;
224 
225     std::shared_ptr<SBuffer> accessUnit;
226 
227     while ((packet = vpx_codec_get_cx_data(mCodecContext.get(), &iter)) !=
228             nullptr) {
229         if (packet->kind == VPX_CODEC_CX_FRAME_PKT) {
230             LOG(VERBOSE)
231                 << "vpx_codec_encode returned packet of size "
232                 << packet->data.frame.sz;
233 
234             if (accessUnit != nullptr) {
235                 LOG(ERROR)
236                     << "vpx_codec_encode returned more than one packet of "
237                         "compressed data!";
238 
239                 return nullptr;
240             }
241 
242             accessUnit.reset(new SBuffer(packet->data.frame.sz));
243 
244             memcpy(accessUnit->data(),
245                    packet->data.frame.buf,
246                    packet->data.frame.sz);
247 
248             accessUnit->time_us(timeUs);
249         } else {
250             LOG(INFO)
251                 << "vpx_codec_encode returned a packet of type "
252                 << packet->kind;
253         }
254     }
255 
256     return accessUnit;
257 }
258 
259 ////////////////////////////////////////////////////////////////////////////////
260 
FrameBufferSource(Format format)261 FrameBufferSource::FrameBufferSource(Format format)
262     : mInitCheck(-ENODEV),
263       mState(STOPPED),
264       mFormat(format),
265       mScreenWidth(0),
266       mScreenHeight(0),
267       mScreenDpi(0),
268       mScreenRate(0),
269       mNumConsumers(0),
270       mOnFrameFn(nullptr) {
271     mInitCheck = 0;
272 }
273 
~FrameBufferSource()274 FrameBufferSource::~FrameBufferSource() {
275     stop();
276 }
277 
initCheck() const278 int32_t FrameBufferSource::initCheck() const {
279     return mInitCheck;
280 }
281 
start()282 int32_t FrameBufferSource::start() {
283     std::lock_guard<std::mutex> autoLock(mLock);
284 
285     if (mState != STOPPED) {
286         return 0;
287     }
288 
289     switch (mFormat) {
290         case Format::VP8:
291         {
292             mEncoder.reset(
293                     new VPXEncoder(mScreenWidth, mScreenHeight, mScreenRate));
294 
295             break;
296         }
297 
298         default:
299             LOG(FATAL) << "Should not be here.";
300     }
301 
302     mState = RUNNING;
303 
304     return 0;
305 }
306 
stop()307 int32_t FrameBufferSource::stop() {
308     std::lock_guard<std::mutex> autoLock(mLock);
309 
310     if (mState == STOPPED) {
311         return 0;
312     }
313 
314     mState = STOPPING;
315 
316     mState = STOPPED;
317 
318     mEncoder.reset();
319 
320     return 0;
321 }
322 
pause()323 int32_t FrameBufferSource::pause() {
324     std::lock_guard<std::mutex> autoLock(mLock);
325 
326     if (mState == PAUSED) {
327         return 0;
328     }
329 
330     if (mState != RUNNING) {
331         return -EINVAL;
332     }
333 
334     mState = PAUSED;
335 
336     LOG(VERBOSE) << "Now paused.";
337 
338     return 0;
339 }
340 
resume()341 int32_t FrameBufferSource::resume() {
342     std::lock_guard<std::mutex> autoLock(mLock);
343 
344     if (mState == RUNNING) {
345         return 0;
346     }
347 
348     if (mState != PAUSED) {
349         return -EINVAL;
350     }
351 
352     mState = RUNNING;
353 
354     LOG(VERBOSE) << "Now running.";
355 
356     return 0;
357 }
358 
paused() const359 bool FrameBufferSource::paused() const {
360     return mState == PAUSED;
361 }
362 
requestIDRFrame()363 int32_t FrameBufferSource::requestIDRFrame() {
364     mEncoder->forceIDRFrame();
365 
366     return 0;
367 }
368 
setScreenParams(const int32_t screenParams[4])369 void FrameBufferSource::setScreenParams(const int32_t screenParams[4]) {
370     mScreenWidth = screenParams[0];
371     mScreenHeight = screenParams[1];
372     mScreenDpi = screenParams[2];
373     mScreenRate = screenParams[3];
374 }
375 
injectFrame(const void * data,size_t size)376 void FrameBufferSource::injectFrame(const void *data, size_t size) {
377     // Only used in the case of CrosVM operation.
378     (void)size;
379 
380     std::lock_guard<std::mutex> autoLock(mLock);
381     if (mState != State::RUNNING) {
382         return;
383     }
384 
385     mEncoder->storeFrame(data);
386     // Only encode and forward the frame when there are consumers connected
387     if (mNumConsumers) {
388         auto accessUnit = mEncoder->encodeStoredFrame(GetNowUs());
389         StreamingSource::onAccessUnit(accessUnit);
390     }
391 }
392 
notifyNewStreamConsumer()393 void FrameBufferSource::notifyNewStreamConsumer() {
394     std::lock_guard<std::mutex> autoLock(mLock);
395     ++mNumConsumers;
396     if (mState != State::RUNNING) {
397         return;
398     }
399 
400     mEncoder->forceIDRFrame();
401     auto accessUnit = mEncoder->encodeStoredFrame(GetNowUs());
402     if (!accessUnit) {
403         // nullptr means there isn't a stored frame to encode.
404         return;
405     }
406 
407     StreamingSource::onAccessUnit(accessUnit);
408 }
409 
notifyStreamConsumerDisconnected()410 void FrameBufferSource::notifyStreamConsumerDisconnected() {
411     std::lock_guard<std::mutex> autoLock(mLock);
412     --mNumConsumers;
413 }
414 
415 }  // namespace android
416