ref: 15a75b45304248f746634b43763c496322bf8968
dir: /vp9/simple_encode.h/
/* * Copyright (c) 2019 The WebM project authors. All Rights Reserved. * * Use of this source code is governed by a BSD-style license * that can be found in the LICENSE file in the root of the source * tree. An additional intellectual property rights grant can be found * in the file PATENTS. All contributing project authors may * be found in the AUTHORS file in the root of the source tree. */ #ifndef VPX_VP9_SIMPLE_ENCODE_H_ #define VPX_VP9_SIMPLE_ENCODE_H_ #include <cstddef> #include <cstdint> #include <cstdio> #include <memory> #include <vector> namespace vp9 { enum StatusCode { StatusOk = 0, StatusError, }; // TODO(angiebird): Add description for each frame type. enum FrameType { kFrameTypeKey = 0, kFrameTypeInter = 1, kFrameTypeAltRef = 2, kFrameTypeOverlay = 3, kFrameTypeGolden = 4, }; // TODO(angiebird): Add description for each reference frame type. // This enum numbers have to be contiguous and start from zero except // kNoneRefFrame. enum RefFrameType { kRefFrameTypeLast = 0, kRefFrameTypePast = 1, kRefFrameTypeFuture = 2, kRefFrameTypeMax = 3, kRefFrameTypeNone = -1, }; enum GopMapFlag { kGopMapFlagStart = 1 << 0, // Indicate this location is the start of a group of pictures. kGopMapFlagUseAltRef = 1 << 1, // Indicate this group of pictures will use an alt ref. Only set // this flag when kGopMapFlagStart is set. }; // The frame is split to 4x4 blocks. // This structure contains the information of each 4x4 block. struct PartitionInfo { int row; // row pixel offset of current 4x4 block int column; // column pixel offset of current 4x4 block int row_start; // row pixel offset of the start of the prediction block int column_start; // column pixel offset of the start of the prediction block int width; // prediction block width int height; // prediction block height }; constexpr int kMotionVectorSubPixelPrecision = 8; constexpr int kMotionVectorFullPixelPrecision = 1; // In the first pass. The frame is split to 16x16 blocks. // This structure contains the information of each 16x16 block. // In the second pass. The frame is split to 4x4 blocks. // This structure contains the information of each 4x4 block. struct MotionVectorInfo { // Number of valid motion vectors, always 0 if this block is in the key frame. // For inter frames, it could be 1 or 2. int mv_count; // The reference frame for motion vectors. If the second motion vector does // not exist (mv_count = 1), the reference frame is kNoneRefFrame. // Otherwise, the reference frame is either kRefFrameTypeLast, or // kRefFrameTypePast, or kRefFrameTypeFuture. RefFrameType ref_frame[2]; // The row offset of motion vectors in the unit of pixel. // If the second motion vector does not exist, the value is 0. double mv_row[2]; // The column offset of motion vectors in the unit of pixel. // If the second motion vector does not exist, the value is 0. double mv_column[2]; }; // Accumulated tpl stats of all blocks in one frame. // For each frame, the tpl stats are computed per 32x32 block. struct TplStatsInfo { // Intra complexity: the sum of absolute transform difference (SATD) of // intra predicted residuals. int64_t intra_cost; // Inter complexity: the SATD of inter predicted residuals. int64_t inter_cost; // Motion compensated information flow. It measures how much information // is propagated from the current frame to other frames. int64_t mc_flow; // Motion compensated dependency cost. It equals to its own intra_cost // plus the mc_flow. int64_t mc_dep_cost; // Motion compensated reference cost. int64_t mc_ref_cost; }; struct RefFrameInfo { int coding_indexes[kRefFrameTypeMax]; // Indicate whether the reference frames are available or not. // When the reference frame type is not valid, it means either the to-be-coded // frame is a key frame or the reference frame already appears in other // reference frame type. vp9 always keeps three types of reference frame // available. However, the duplicated reference frames will not be // chosen by the encoder. The priorities of choosing reference frames are // kRefFrameTypeLast > kRefFrameTypePast > kRefFrameTypeFuture. // For example, if kRefFrameTypeLast and kRefFrameTypePast both point to the // same frame, kRefFrameTypePast will be set to invalid. // 1: the ref frame type is available 0: the ref frame type is not available int valid_list[kRefFrameTypeMax]; }; bool operator==(const RefFrameInfo &a, const RefFrameInfo &b); struct EncodeFrameInfo { int show_idx; // Each show or no show frame is assigned with a coding index based on its // coding order (starting from zero) in the coding process of the entire // video. The coding index for each frame is unique. int coding_index; RefFrameInfo ref_frame_info; FrameType frame_type; }; // This structure is a copy of vp9 |nmv_component_counts|. struct NewMotionvectorComponentCounts { std::vector<unsigned int> sign; std::vector<unsigned int> classes; std::vector<unsigned int> class0; std::vector<std::vector<unsigned int>> bits; std::vector<std::vector<unsigned int>> class0_fp; std::vector<unsigned int> fp; std::vector<unsigned int> class0_hp; std::vector<unsigned int> hp; }; // This structure is a copy of vp9 |nmv_context_counts|. struct NewMotionVectorContextCounts { std::vector<unsigned int> joints; std::vector<NewMotionvectorComponentCounts> comps; }; using UintArray2D = std::vector<std::vector<unsigned int>>; using UintArray3D = std::vector<std::vector<std::vector<unsigned int>>>; using UintArray5D = std::vector< std::vector<std::vector<std::vector<std::vector<unsigned int>>>>>; using UintArray6D = std::vector<std::vector< std::vector<std::vector<std::vector<std::vector<unsigned int>>>>>>; // This structure is a copy of vp9 |tx_counts|. struct TransformSizeCounts { // Transform size found in blocks of partition size 32x32. // First dimension: transform size contexts (2). // Second dimension: transform size type (3: 32x32, 16x16, 8x8) UintArray2D p32x32; // Transform size found in blocks of partition size 16x16. // First dimension: transform size contexts (2). // Second dimension: transform size type (2: 16x16, 8x8) UintArray2D p16x16; // Transform size found in blocks of partition size 8x8. // First dimension: transform size contexts (2). // Second dimension: transform size type (1: 8x8) UintArray2D p8x8; // Overall transform size count. std::vector<unsigned int> tx_totals; }; // This structure is a copy of vp9 |FRAME_COUNTS|. struct FrameCounts { // Intra prediction mode for luma plane. First dimension: block size (4). // Second dimension: intra prediction mode (10). UintArray2D y_mode; // Intra prediction mode for chroma plane. First and second dimension: // intra prediction mode (10). UintArray2D uv_mode; // Partition type. First dimension: partition contexts (16). // Second dimension: partition type (4). UintArray2D partition; // Transform coefficient. UintArray6D coef; // End of block (the position of the last non-zero transform coefficient) UintArray5D eob_branch; // Interpolation filter type. First dimension: switchable filter contexts (4). // Second dimension: filter types (3). UintArray2D switchable_interp; // Inter prediction mode (the motion vector type). // First dimension: inter mode contexts (7). // Second dimension: mode type (4). UintArray2D inter_mode; // Block is intra or inter predicted. First dimension: contexts (4). // Second dimension: type (0 for intra, 1 for inter). UintArray2D intra_inter; // Block is compound predicted (predicted from average of two blocks). // First dimension: contexts (5). // Second dimension: type (0 for single, 1 for compound prediction). UintArray2D comp_inter; // Type of the reference frame. Only one reference frame. // First dimension: context (5). Second dimension: context (2). // Third dimension: count (2). UintArray3D single_ref; // Type of the two reference frames. // First dimension: context (5). Second dimension: count (2). UintArray2D comp_ref; // Block skips transform and quantization, uses prediction as reconstruction. // First dimension: contexts (3). Second dimension: type (0 not skip, 1 skip). UintArray2D skip; // Transform size. TransformSizeCounts tx; // New motion vector. NewMotionVectorContextCounts mv; }; struct ImageBuffer { // The image data is stored in raster order, // i.e. image[plane][r][c] = // plane_buffer[plane][r * plane_width[plane] + plane_height[plane]]. std::unique_ptr<unsigned char[]> plane_buffer[3]; int plane_width[3]; int plane_height[3]; }; void output_image_buffer(const ImageBuffer &image_buffer, std::FILE *out_file); struct EncodeFrameResult { int show_idx; FrameType frame_type; int coding_idx; RefFrameInfo ref_frame_info; size_t coding_data_bit_size; size_t coding_data_byte_size; // The EncodeFrame will allocate a buffer, write the coding data into the // buffer and give the ownership of the buffer to coding_data. std::unique_ptr<unsigned char[]> coding_data; double psnr; uint64_t sse; int quantize_index; FrameCounts frame_counts; int num_rows_4x4; // number of row units, in size of 4. int num_cols_4x4; // number of column units, in size of 4. // A vector of the partition information of the frame. // The number of elements is |num_rows_4x4| * |num_cols_4x4|. // The frame is divided 4x4 blocks of |num_rows_4x4| rows and // |num_cols_4x4| columns. // Each 4x4 block contains the current pixel position (|row|, |column|), // the start pixel position of the partition (|row_start|, |column_start|), // and the |width|, |height| of the partition. // The current pixel position can be the same as the start pixel position // if the 4x4 block is the top-left block in the partition. Otherwise, they // are different. // Within the same partition, all 4x4 blocks have the same |row_start|, // |column_start|, |width| and |height|. // For example, if the frame is partitioned to a 32x32 block, // starting at (0, 0). Then, there're 64 4x4 blocks within this partition. // They all have the same |row_start|, |column_start|, |width|, |height|, // which can be used to figure out the start of the current partition and // the start of the next partition block. // Horizontal next: |column_start| + |width|, // Vertical next: |row_start| + |height|. std::vector<PartitionInfo> partition_info; // A vector of the motion vector information of the frame. // The number of elements is |num_rows_4x4| * |num_cols_4x4|. // The frame is divided into 4x4 blocks of |num_rows_4x4| rows and // |num_cols_4x4| columns. // Each 4x4 block contains 0 motion vector if this is an intra predicted // frame (for example, the key frame). If the frame is inter predicted, // each 4x4 block contains either 1 or 2 motion vectors. // Similar to partition info, all 4x4 blocks inside the same partition block // share the same motion vector information. std::vector<MotionVectorInfo> motion_vector_info; // A vector of the tpl stats information. // The tpl stats measure the complexity of a frame, as well as the // information propagated along the motion trajectory between frames, in // the reference frame structure. // The tpl stats could be used as a more accurate spatial and temporal // complexity measure in addition to the first pass stats. // The vector contains tpl stats for all show frames in a GOP. // The tpl stats stored in the vector is according to the encoding order. // For example, suppose there are N show frames for the current GOP. // Then tpl_stats_info[0] stores the information of the first frame to be // encoded for this GOP, i.e, the AltRef frame. std::vector<TplStatsInfo> tpl_stats_info; ImageBuffer coded_frame; // recode_count, q_index_history and rate_history are only available when // EncodeFrameWithTargetFrameBits() is used. int recode_count; std::vector<int> q_index_history; std::vector<int> rate_history; }; struct GroupOfPicture { // This list will be updated internally in StartEncode() and // EncodeFrame()/EncodeFrameWithQuantizeIndex(). // In EncodeFrame()/EncodeFrameWithQuantizeIndex(), the update will only be // triggered when the coded frame is the last one in the previous group of // pictures. std::vector<EncodeFrameInfo> encode_frame_list; // Indicates the index of the next coding frame in encode_frame_list. // In other words, EncodeFrameInfo of the next coding frame can be // obtained with encode_frame_list[next_encode_frame_index]. // Internally, next_encode_frame_index will be set to zero after the last // frame of the group of pictures is coded. Otherwise, next_encode_frame_index // will be increased after each EncodeFrame()/EncodeFrameWithQuantizeIndex() // call. int next_encode_frame_index; // Number of show frames in this group of pictures. int show_frame_count; // The show index/timestamp of the earliest show frame in the group of // pictures. int start_show_index; // The coding index of the first coding frame in the group of pictures. int start_coding_index; // Indicates whether this group of pictures starts with a key frame. int first_is_key_frame; // Indicates whether this group of pictures uses an alt ref. int use_alt_ref; // Indicates whether previous group of pictures used an alt ref. int last_gop_use_alt_ref; }; class SimpleEncode { public: // When outfile_path is set, the encoder will output the bitstream in ivf // format. SimpleEncode(int frame_width, int frame_height, int frame_rate_num, int frame_rate_den, int target_bitrate, int num_frames, const char *infile_path, const char *outfile_path = nullptr); ~SimpleEncode(); SimpleEncode(SimpleEncode &) = delete; SimpleEncode &operator=(const SimpleEncode &) = delete; // Adjusts the encoder's coding speed. // If this function is not called, the encoder will use default encode_speed // 0. Call this function before ComputeFirstPassStats() if needed. // The encode_speed is equivalent to --cpu-used of the vpxenc command. // The encode_speed's range should be [0, 9]. // Setting the encode_speed to a higher level will yield faster coding // at the cost of lower compression efficiency. void SetEncodeSpeed(int encode_speed); // Set encoder config // The following configs in VP9EncoderConfig are allowed to change in this // function. See https://ffmpeg.org/ffmpeg-codecs.html#libvpx for each // config's meaning. // Configs in VP9EncoderConfig: Equivalent configs in ffmpeg: // 1 key_freq -g // 2 two_pass_vbrmin_section -minrate * 100LL / bit_rate // 3 two_pass_vbrmax_section -maxrate * 100LL / bit_rate // 4 under_shoot_pct -undershoot-pct // 5 over_shoot_pct -overshoot-pct // 6 max_threads -threads // 7 frame_parallel_decoding_mode -frame-parallel // 8 tile_column -tile-columns // 9 arnr_max_frames -arnr-maxframes // 10 arnr_strength -arnr-strength // 11 lag_in_frames -rc_lookahead // 12 encode_breakout -static-thresh // 13 enable_tpl_model -enable-tpl // 14 enable_auto_arf -auto-alt-ref // 15 rc_mode // Possible Settings: // 0 - Variable Bit Rate (VPX_VBR) -b:v <bit_rate> // 1 - Constant Bit Rate (VPX_CBR) -b:v <bit_rate> -minrate <bit_rate> // -maxrate <bit_rate> // two_pass_vbrmin_section == 100 i.e. bit_rate == minrate == maxrate // two_pass_vbrmax_section == 100 // 2 - Constrained Quality (VPX_CQ) -crf <cq_level> -b:v bit_rate // 3 - Constant Quality (VPX_Q) -crf <cq_level> -b:v 0 // See https://trac.ffmpeg.org/wiki/Encode/VP9 for more details. // 16 cq_level see rc_mode for details. StatusCode SetEncodeConfig(const char *name, const char *value); // A debug function that dumps configs from VP9EncoderConfig // pass = 1: first pass, pass = 2: second pass // fp: file pointer for dumping config StatusCode DumpEncodeConfigs(int pass, FILE *fp); // Makes encoder compute the first pass stats and store it at // impl_ptr_->first_pass_stats. key_frame_map_ is also computed based on the // first pass stats. void ComputeFirstPassStats(); // Outputs the first pass stats represented by a 2-D vector. // One can use the frame index at first dimension to retrieve the stats for // each video frame. The stats of each video frame is a vector of 25 double // values. For details, please check FIRSTPASS_STATS in vp9_firstpass.h std::vector<std::vector<double>> ObserveFirstPassStats(); // Outputs the first pass motion vectors represented by a 2-D vector. // One can use the frame index at first dimension to retrieve the mvs for // each video frame. The frame is divided into 16x16 blocks. The number of // elements is round_up(|num_rows_4x4| / 4) * round_up(|num_cols_4x4| / 4). std::vector<std::vector<MotionVectorInfo>> ObserveFirstPassMotionVectors(); // Ouputs a copy of key_frame_map_, a binary vector with size equal to the // number of show frames in the video. For each entry in the vector, 1 // indicates the position is a key frame and 0 indicates it's not a key frame. // This function should be called after ComputeFirstPassStats() std::vector<int> ObserveKeyFrameMap() const; // Sets group of pictures map for coding the entire video. // Each entry in the gop_map corresponds to a show frame in the video. // Therefore, the size of gop_map should equal to the number of show frames in // the entire video. // If a given entry's kGopMapFlagStart is set, it means this is the start of a // gop. Once kGopMapFlagStart is set, one can set kGopMapFlagUseAltRef to // indicate whether this gop use altref. // If a given entry is zero, it means it's in the middle of a gop. // This function should be called only once after ComputeFirstPassStats(), // before StartEncode(). // This API will check and modify the gop_map to satisfy the following // constraints. // 1) Each key frame position should be at the start of a gop. // 2) The last gop should not use an alt ref. void SetExternalGroupOfPicturesMap(int *gop_map, int gop_map_size); // Observe the group of pictures map set through // SetExternalGroupOfPicturesMap(). This function should be called after // SetExternalGroupOfPicturesMap(). std::vector<int> ObserveExternalGroupOfPicturesMap(); // Initializes the encoder for actual encoding. // This function should be called after ComputeFirstPassStats(). void StartEncode(); // Frees the encoder. // This function should be called after StartEncode() or EncodeFrame(). void EndEncode(); // The key frame group size includes one key frame plus the number of // following inter frames. Note that the key frame group size only counts the // show frames. The number of no show frames like alternate refereces are not // counted. int GetKeyFrameGroupSize() const; // Provides the group of pictures that the next coding frame is in. // Only call this function between StartEncode() and EndEncode() GroupOfPicture ObserveGroupOfPicture() const; // Gets encode_frame_info for the next coding frame. // Only call this function between StartEncode() and EndEncode() EncodeFrameInfo GetNextEncodeFrameInfo() const; // Encodes a frame // This function should be called after StartEncode() and before EndEncode(). void EncodeFrame(EncodeFrameResult *encode_frame_result); // Encodes a frame with a specific quantize index. // This function should be called after StartEncode() and before EndEncode(). void EncodeFrameWithQuantizeIndex(EncodeFrameResult *encode_frame_result, int quantize_index); // Encode a frame with target frame bits usage. // The encoder will find a quantize index to make the actual frame bits usage // match the target. EncodeFrameWithTargetFrameBits() will recode the frame // up to 7 times to find a q_index to make the actual_frame_bits satisfy the // following inequality. |actual_frame_bits - target_frame_bits| * 100 / // target_frame_bits // <= percent_diff. void EncodeFrameWithTargetFrameBits(EncodeFrameResult *encode_frame_result, int target_frame_bits, double percent_diff); // Gets the number of coding frames for the video. The coding frames include // show frame and no show frame. // This function should be called after ComputeFirstPassStats(). int GetCodingFrameNum() const; // Gets the total number of pixels of YUV planes per frame. uint64_t GetFramePixelCount() const; private: // Compute the key frame locations of the video based on first pass stats. // The results are returned as a binary vector with 1s indicating keyframes // and 0s indicating non keyframes. // It has to be called after impl_ptr_->first_pass_stats is computed. std::vector<int> ComputeKeyFrameMap() const; // Updates key_frame_group_size_, reset key_frame_group_index_ and init // ref_frame_info_. void UpdateKeyFrameGroup(int key_frame_show_index); // Update key_frame_group_index_. void PostUpdateKeyFrameGroupIndex(FrameType frame_type); void PostUpdateState(const EncodeFrameResult &encode_frame_result); class EncodeImpl; int frame_width_; // frame width in pixels. int frame_height_; // frame height in pixels. int frame_rate_num_; int frame_rate_den_; int target_bitrate_; int num_frames_; int encode_speed_; std::FILE *in_file_; std::FILE *out_file_; std::unique_ptr<EncodeImpl> impl_ptr_; std::vector<int> key_frame_map_; std::vector<int> gop_map_; GroupOfPicture group_of_picture_; // The key frame group size includes one key frame plus the number of // following inter frames. Note that the key frame group size only counts the // show frames. The number of no show frames like alternate references are not // counted. int key_frame_group_size_; // The index for the to-be-coded show frame in the key frame group. int key_frame_group_index_; // Each show or no show frame is assigned with a coding index based on its // coding order (starting from zero) in the coding process of the entire // video. The coding index of the to-be-coded frame. int frame_coding_index_; // Number of show frames we have coded so far. int show_frame_count_; // TODO(angiebird): Do we need to reset ref_frames_info_ when the next key // frame appears? // Reference frames info of the to-be-coded frame. RefFrameInfo ref_frame_info_; // A 2-D vector of motion vector information of the frame collected // from the first pass. The first dimension is the frame index. // Each frame is divided into 16x16 blocks. The number of elements is // round_up(|num_rows_4x4| / 4) * round_up(|num_cols_4x4| / 4). // Each 16x16 block contains 0 motion vector if this is an intra predicted // frame (for example, the key frame). If the frame is inter predicted, // each 16x16 block contains either 1 or 2 motion vectors. // The first motion vector is always from the LAST_FRAME. // The second motion vector is always from the GOLDEN_FRAME. std::vector<std::vector<MotionVectorInfo>> fp_motion_vector_info_; }; } // namespace vp9 #endif // VPX_VP9_SIMPLE_ENCODE_H_