media/filters/decrypting_video_decoder.cc

   1 // Copyright 2012 The Chromium Authors
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "media/filters/decrypting_video_decoder.h"
   6
   7 #include "base/functional/bind.h"
   8 #include "base/functional/callback_helpers.h"
   9 #include "base/location.h"
  10 #include "base/logging.h"
  11 #include "base/strings/string_number_conversions.h"
  12 #include "base/task/bind_post_task.h"
  13 #include "base/task/sequenced_task_runner.h"
  14 #include "base/trace_event/trace_event.h"
  15 #include "media/base/cdm_context.h"
  16 #include "media/base/decoder_buffer.h"
  17 #include "media/base/media_log.h"
  18 #include "media/base/video_frame.h"
  19
  20 namespace media {
  21
  22 const char DecryptingVideoDecoder::kDecoderName[] = "DecryptingVideoDecoder";
  23
  24 DecryptingVideoDecoder::DecryptingVideoDecoder(
  25     const scoped_refptr<base::SequencedTaskRunner>& task_runner,
  26     MediaLog* media_log)
  27     : task_runner_(task_runner), media_log_(media_log) {
  28   DETACH_FROM_SEQUENCE(sequence_checker_);
  29 }
  30
  31 VideoDecoderType DecryptingVideoDecoder::GetDecoderType() const {
  32   return VideoDecoderType::kDecrypting;
  33 }
  34
  35 void DecryptingVideoDecoder::Initialize(const VideoDecoderConfig& config,
  36                                         bool /* low_delay */,
  37                                         CdmContext* cdm_context,
  38                                         InitCB init_cb,
  39                                         const OutputCB& output_cb,
  40                                         const WaitingCB& waiting_cb) {
  41   DVLOG(2) << __func__ << ": " << config.AsHumanReadableString();
  42
  43   DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
  44   DCHECK(state_ == kUninitialized || state_ == kIdle ||
  45          state_ == kDecodeFinished)
  46       << state_;
  47   DCHECK(!decode_cb_);
  48   DCHECK(!reset_cb_);
  49   DCHECK(config.IsValidConfig());
  50
  51   init_cb_ = base::BindPostTaskToCurrentDefault(std::move(init_cb));
  52
  53   if (!cdm_context) {
  54     // Once we have a CDM context, one should always be present.
  55     DCHECK(!support_clear_content_);
  56     std::move(init_cb_).Run(DecoderStatus::Codes::kUnsupportedEncryptionMode);
  57     return;
  58   }
  59
  60   if (!config.is_encrypted() && !support_clear_content_) {
  61     std::move(init_cb_).Run(DecoderStatus::Codes::kUnsupportedEncryptionMode);
  62     return;
  63   }
  64
  65   // Once initialized with encryption support, the value is sticky, so we'll use
  66   // the decryptor for clear content as well.
  67   support_clear_content_ = true;
  68
  69   output_cb_ = base::BindPostTaskToCurrentDefault(output_cb);
  70   config_ = config;
  71
  72   DCHECK(waiting_cb);
  73   waiting_cb_ = waiting_cb;
  74
  75   if (state_ == kUninitialized) {
  76     if (!cdm_context->GetDecryptor()) {
  77       DVLOG(1) << __func__ << ": no decryptor";
  78       std::move(init_cb_).Run(DecoderStatus::Codes::kUnsupportedEncryptionMode);
  79       return;
  80     }
  81
  82     decryptor_ = cdm_context->GetDecryptor();
  83     event_cb_registration_ = cdm_context->RegisterEventCB(
  84         base::BindRepeating(&DecryptingVideoDecoder::OnCdmContextEvent,
  85                             weak_factory_.GetWeakPtr()));
  86   } else {
  87     // Reinitialization (i.e. upon a config change). The new config can be
  88     // encrypted or clear.
  89     decryptor_->DeinitializeDecoder(Decryptor::kVideo);
  90   }
  91
  92   state_ = kPendingDecoderInit;
  93   decryptor_->InitializeVideoDecoder(
  94       config_, base::BindPostTaskToCurrentDefault(
  95                    base::BindOnce(&DecryptingVideoDecoder::FinishInitialization,
  96                                   weak_factory_.GetWeakPtr())));
  97 }
  98
  99 bool DecryptingVideoDecoder::SupportsDecryption() const {
 100   return true;
 101 }
 102
 103 void DecryptingVideoDecoder::Decode(scoped_refptr<DecoderBuffer> buffer,
 104                                     DecodeCB decode_cb) {
 105   DVLOG(3) << "Decode()";
 106   DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
 107   DCHECK(state_ == kIdle || state_ == kDecodeFinished || state_ == kError)
 108       << state_;
 109   DCHECK(decode_cb);
 110   CHECK(!decode_cb_) << "Overlapping decodes are not supported.";
 111
 112   decode_cb_ = base::BindPostTaskToCurrentDefault(std::move(decode_cb));
 113
 114   if (state_ == kError) {
 115     std::move(decode_cb_).Run(DecoderStatus::Codes::kPlatformDecodeFailure);
 116     return;
 117   }
 118
 119   // Return empty frames if decoding has finished.
 120   if (state_ == kDecodeFinished) {
 121     std::move(decode_cb_).Run(DecoderStatus::Codes::kOk);
 122     return;
 123   }
 124
 125   pending_buffer_to_decode_ = std::move(buffer);
 126   state_ = kPendingDecode;
 127   DecodePendingBuffer();
 128 }
 129
 130 void DecryptingVideoDecoder::Reset(base::OnceClosure closure) {
 131   DVLOG(2) << "Reset() - state: " << state_;
 132   DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
 133   DCHECK(state_ == kIdle || state_ == kPendingDecode ||
 134          state_ == kWaitingForKey || state_ == kDecodeFinished ||
 135          state_ == kError)
 136       << state_;
 137   DCHECK(!init_cb_);  // No Reset() during pending initialization.
 138   DCHECK(!reset_cb_);
 139
 140   reset_cb_ = base::BindPostTaskToCurrentDefault(std::move(closure));
 141
 142   decryptor_->ResetDecoder(Decryptor::kVideo);
 143
 144   // Reset() cannot complete if the decode callback is still pending.
 145   // Defer the resetting process in this case. The |reset_cb_| will be fired
 146   // after the decode callback is fired - see DecryptAndDecodeBuffer() and
 147   // DeliverFrame().
 148   if (state_ == kPendingDecode) {
 149     DCHECK(decode_cb_);
 150     return;
 151   }
 152
 153   if (state_ == kWaitingForKey) {
 154     CompleteWaitingForDecryptionKey();
 155     DCHECK(decode_cb_);
 156     pending_buffer_to_decode_.reset();
 157     std::move(decode_cb_).Run(DecoderStatus::Codes::kAborted);
 158   }
 159
 160   DCHECK(!decode_cb_);
 161   DoReset();
 162 }
 163
 164 DecryptingVideoDecoder::~DecryptingVideoDecoder() {
 165   DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
 166
 167   if (state_ == kUninitialized)
 168     return;
 169
 170   if (state_ == kWaitingForKey)
 171     CompleteWaitingForDecryptionKey();
 172   if (state_ == kPendingDecode)
 173     CompletePendingDecode(Decryptor::kError);
 174
 175   if (decryptor_) {
 176     decryptor_->DeinitializeDecoder(Decryptor::kVideo);
 177     decryptor_ = nullptr;
 178   }
 179   pending_buffer_to_decode_.reset();
 180   if (init_cb_)
 181     std::move(init_cb_).Run(DecoderStatus::Codes::kInterrupted);
 182   if (decode_cb_)
 183     std::move(decode_cb_).Run(DecoderStatus::Codes::kAborted);
 184   if (reset_cb_)
 185     std::move(reset_cb_).Run();
 186 }
 187
 188 void DecryptingVideoDecoder::FinishInitialization(bool success) {
 189   DVLOG(2) << "FinishInitialization()";
 190   DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
 191   DCHECK_EQ(state_, kPendingDecoderInit) << state_;
 192   DCHECK(init_cb_);
 193   DCHECK(!reset_cb_);   // No Reset() before initialization finished.
 194   DCHECK(!decode_cb_);  // No Decode() before initialization finished.
 195
 196   if (!success) {
 197     DVLOG(1) << __func__ << ": failed to init video decoder on decryptor";
 198     // TODO(*) Is there a better reason? Should this method itself take a
 199     // status?
 200     std::move(init_cb_).Run(DecoderStatus::Codes::kFailed);
 201     decryptor_ = nullptr;
 202     event_cb_registration_.reset();
 203     state_ = kError;
 204     return;
 205   }
 206
 207   // Success!
 208   state_ = kIdle;
 209   std::move(init_cb_).Run(DecoderStatus::Codes::kOk);
 210 }
 211
 212 void DecryptingVideoDecoder::DecodePendingBuffer() {
 213   DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
 214   DCHECK_EQ(state_, kPendingDecode) << state_;
 215
 216   // Note: Traces require a unique ID per decode, if we ever support multiple
 217   // in flight decodes, the trace begin+end macros need the same unique id.
 218   DCHECK_EQ(GetMaxDecodeRequests(), 1);
 219   TRACE_EVENT_ASYNC_BEGIN1(
 220       "media", "DecryptingVideoDecoder::DecodePendingBuffer", this,
 221       "timestamp_us",
 222       pending_buffer_to_decode_->end_of_stream()
 223           ? 0
 224           : pending_buffer_to_decode_->timestamp().InMicroseconds());
 225
 226   if (!DecoderBuffer::DoSubsamplesMatch(*pending_buffer_to_decode_)) {
 227     MEDIA_LOG(ERROR, media_log_)
 228         << "DecryptingVideoDecoder: Subsamples for Buffer do not match";
 229     state_ = kError;
 230     std::move(decode_cb_).Run(DecoderStatus::Codes::kPlatformDecodeFailure);
 231     return;
 232   }
 233
 234   decryptor_->DecryptAndDecodeVideo(
 235       pending_buffer_to_decode_,
 236       base::BindPostTaskToCurrentDefault(base::BindRepeating(
 237           &DecryptingVideoDecoder::DeliverFrame, weak_factory_.GetWeakPtr())));
 238 }
 239
 240 void DecryptingVideoDecoder::DeliverFrame(Decryptor::Status status,
 241                                           scoped_refptr<VideoFrame> frame) {
 242   DVLOG(3) << "DeliverFrame() - status: " << status;
 243   DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
 244   DCHECK_EQ(state_, kPendingDecode) << state_;
 245   DCHECK(decode_cb_);
 246   DCHECK(pending_buffer_to_decode_.get());
 247   CompletePendingDecode(status);
 248
 249   bool need_to_try_again_if_nokey_is_returned = key_added_while_decode_pending_;
 250   key_added_while_decode_pending_ = false;
 251
 252   scoped_refptr<DecoderBuffer> scoped_pending_buffer_to_decode =
 253       std::move(pending_buffer_to_decode_);
 254
 255   if (reset_cb_) {
 256     std::move(decode_cb_).Run(DecoderStatus::Codes::kAborted);
 257     DoReset();
 258     return;
 259   }
 260
 261   DCHECK_EQ(status == Decryptor::kSuccess, frame.get() != nullptr);
 262
 263   if (status == Decryptor::kError) {
 264     DVLOG(2) << "DeliverFrame() - kError";
 265     MEDIA_LOG(ERROR, media_log_) << GetDecoderType() << ": decode error";
 266     state_ = kError;
 267     std::move(decode_cb_).Run(DecoderStatus::Codes::kPlatformDecodeFailure);
 268     return;
 269   }
 270
 271   if (status == Decryptor::kNoKey) {
 272     std::string key_id =
 273         scoped_pending_buffer_to_decode->decrypt_config()->key_id();
 274     std::string log_message =
 275         "no key for key ID " + base::HexEncode(key_id.data(), key_id.size()) +
 276         "; will resume decoding after new usable key is available";
 277     DVLOG(1) << __func__ << ": " << log_message;
 278     MEDIA_LOG(INFO, media_log_) << GetDecoderType() << ": " << log_message;
 279
 280     // Set |pending_buffer_to_decode_| back as we need to try decoding the
 281     // pending buffer again when new key is added to the decryptor.
 282     pending_buffer_to_decode_ = std::move(scoped_pending_buffer_to_decode);
 283
 284     if (need_to_try_again_if_nokey_is_returned) {
 285       // The |state_| is still kPendingDecode.
 286       MEDIA_LOG(INFO, media_log_)
 287           << GetDecoderType() << ": key was added, resuming decode";
 288       DecodePendingBuffer();
 289       return;
 290     }
 291
 292     TRACE_EVENT_ASYNC_BEGIN0(
 293         "media", "DecryptingVideoDecoder::WaitingForDecryptionKey", this);
 294     state_ = kWaitingForKey;
 295     waiting_cb_.Run(WaitingReason::kNoDecryptionKey);
 296     return;
 297   }
 298
 299   if (status == Decryptor::kNeedMoreData) {
 300     DVLOG(2) << "DeliverFrame() - kNeedMoreData";
 301     state_ = scoped_pending_buffer_to_decode->end_of_stream() ? kDecodeFinished
 302                                                               : kIdle;
 303     std::move(decode_cb_).Run(DecoderStatus::Codes::kOk);
 304     return;
 305   }
 306
 307   DCHECK_EQ(status, Decryptor::kSuccess);
 308   CHECK(frame);
 309
 310   // Frame returned with kSuccess should not be an end-of-stream frame.
 311   DCHECK(!frame->metadata().end_of_stream);
 312
 313   // If color space is not set, use the color space in the |config_|.
 314   if (!frame->ColorSpace().IsValid()) {
 315     DVLOG(3) << "Setting color space using information in the config.";
 316     if (config_.color_space_info().IsSpecified())
 317       frame->set_color_space(config_.color_space_info().ToGfxColorSpace());
 318   }
 319
 320   output_cb_.Run(std::move(frame));
 321
 322   if (scoped_pending_buffer_to_decode->end_of_stream()) {
 323     // Set |pending_buffer_to_decode_| back as we need to keep flushing the
 324     // decryptor.
 325     pending_buffer_to_decode_ = std::move(scoped_pending_buffer_to_decode);
 326     DecodePendingBuffer();
 327     return;
 328   }
 329
 330   state_ = kIdle;
 331   std::move(decode_cb_).Run(DecoderStatus::Codes::kOk);
 332 }
 333
 334 void DecryptingVideoDecoder::OnCdmContextEvent(CdmContext::Event event) {
 335   DVLOG(2) << __func__;
 336   DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
 337
 338   if (event != CdmContext::Event::kHasAdditionalUsableKey)
 339     return;
 340
 341   if (state_ == kPendingDecode) {
 342     key_added_while_decode_pending_ = true;
 343     return;
 344   }
 345
 346   if (state_ == kWaitingForKey) {
 347     CompleteWaitingForDecryptionKey();
 348     MEDIA_LOG(INFO, media_log_)
 349         << GetDecoderType() << ": key added, resuming decode";
 350     state_ = kPendingDecode;
 351     DecodePendingBuffer();
 352   }
 353 }
 354
 355 void DecryptingVideoDecoder::DoReset() {
 356   DCHECK(!init_cb_);
 357   DCHECK(!decode_cb_);
 358   state_ = kIdle;
 359   std::move(reset_cb_).Run();
 360 }
 361
 362 void DecryptingVideoDecoder::CompletePendingDecode(Decryptor::Status status) {
 363   DCHECK_EQ(state_, kPendingDecode);
 364   TRACE_EVENT_ASYNC_END1("media", "DecryptingVideoDecoder::DecodePendingBuffer",
 365                          this, "status", Decryptor::GetStatusName(status));
 366 }
 367
 368 void DecryptingVideoDecoder::CompleteWaitingForDecryptionKey() {
 369   DCHECK_EQ(state_, kWaitingForKey);
 370   TRACE_EVENT_ASYNC_END0(
 371       "media", "DecryptingVideoDecoder::WaitingForDecryptionKey", this);
 372 }
 373
 374 }  // namespace media