/*

 * Copyright (c) 2016, Alliance for Open Media. All rights reserved.

 *

 * This source code is subject to the terms of the BSD 2 Clause License and

 * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License

 * was not distributed with this source code in the LICENSE file, you can

 * obtain it at www.aomedia.org/license/software. If the Alliance for Open

 * Media Patent License 1.0 was not distributed with this source code in the

 * PATENTS file, you can obtain it at www.aomedia.org/license/patent.

 */

#include <stdlib.h>

#include <string.h>

#include "config/aom_config.h"

#include "config/aom_version.h"

#include "aom/internal/aom_codec_internal.h"

#include "aom/internal/aom_image_internal.h"

#include "aom/aomdx.h"

#include "aom/aom_decoder.h"

#include "aom/aom_image.h"

#include "aom_dsp/bitreader_buffer.h"

#include "aom_dsp/aom_dsp_common.h"

#include "aom_ports/mem.h"

#include "aom_ports/mem_ops.h"

#include "aom_util/aom_pthread.h"

#include "aom_util/aom_thread.h"

#include "av1/common/alloccommon.h"

#include "av1/common/av1_common_int.h"

#include "av1/common/frame_buffers.h"

#include "av1/common/enums.h"

#include "av1/common/obu_util.h"

#include "av1/decoder/decoder.h"

#include "av1/decoder/decodeframe.h"

#include "av1/decoder/dthread.h"

#include "av1/decoder/grain_synthesis.h"

#include "av1/decoder/obu.h"

#include "av1/av1_iface_common.h"

struct aom_codec_alg_priv {

  aom_codec_priv_t base;

  aom_codec_dec_cfg_t cfg;

  aom_codec_stream_info_t si;

  aom_image_t img;

  int img_avail;

  int flushed;

  int invert_tile_order;

  RefCntBuffer *last_show_frame;  // Last output frame buffer

  int byte_alignment;

  int skip_loop_filter;

  int skip_film_grain;

  int decode_tile_row;

  int decode_tile_col;

  unsigned int tile_mode;

  unsigned int ext_tile_debug;

  unsigned int row_mt;

  EXTERNAL_REFERENCES ext_refs;

  unsigned int is_annexb;

  int operating_point;

  int output_all_layers;

  unsigned int frame_size_limit;

  AVxWorker *frame_worker;

  aom_image_t image_with_grain;

  aom_codec_frame_buffer_t grain_image_frame_buffers[MAX_NUM_SPATIAL_LAYERS];

  size_t num_grain_image_frame_buffers;

  int need_resync;  // wait for key/intra-only frame

  // BufferPool that holds all reference frames. Shared by all the FrameWorkers.

  BufferPool *buffer_pool;

  // External frame buffer info to save for AV1 common.

  void *ext_priv;  // Private data associated with the external frame buffers.

  aom_get_frame_buffer_cb_fn_t get_ext_fb_cb;

  aom_release_frame_buffer_cb_fn_t release_ext_fb_cb;

#if CONFIG_INSPECTION

  aom_inspect_cb inspect_cb;

  void *inspect_ctx;

#endif

};

static aom_codec_err_t decoder_init(aom_codec_ctx_t *ctx) {

  // This function only allocates space for the aom_codec_alg_priv_t

  // structure. More memory may be required at the time the stream

  // information becomes known.

  if (!ctx->priv) {

    aom_codec_alg_priv_t *const priv =

        (aom_codec_alg_priv_t *)aom_calloc(1, sizeof(*priv));

    if (priv == NULL) return AOM_CODEC_MEM_ERROR;

    ctx->priv = (aom_codec_priv_t *)priv;

    ctx->priv->init_flags = ctx->init_flags;

    priv->flushed = 0;

    // TODO(tdaede): this should not be exposed to the API

    priv->cfg.allow_lowbitdepth = !FORCE_HIGHBITDEPTH_DECODING;

    if (ctx->config.dec) {

      priv->cfg = *ctx->config.dec;

      ctx->config.dec = &priv->cfg;

    }

    priv->num_grain_image_frame_buffers = 0;

    // Turn row_mt on by default.

    priv->row_mt = 1;

    // Turn on normal tile coding mode by default.

    // 0 is for normal tile coding mode, and 1 is for large scale tile coding

    // mode(refer to lightfield example).

    priv->tile_mode = 0;

    priv->decode_tile_row = -1;

    priv->decode_tile_col = -1;

    priv->frame_size_limit = 0;

  }

  return AOM_CODEC_OK;

}

static aom_codec_err_t decoder_destroy(aom_codec_alg_priv_t *ctx) {

  if (ctx->frame_worker != NULL) {

    AVxWorker *const worker = ctx->frame_worker;

    aom_get_worker_interface()->end(worker);

    FrameWorkerData *const frame_worker_data = (FrameWorkerData *)worker->data1;

    if (frame_worker_data != NULL && frame_worker_data->pbi != NULL) {

      AV1Decoder *const pbi = frame_worker_data->pbi;

      aom_free(pbi->common.tpl_mvs);

      pbi->common.tpl_mvs = NULL;

      av1_remove_common(&pbi->common);

      av1_free_cdef_buffers(&pbi->common, &pbi->cdef_worker, &pbi->cdef_sync);

      av1_free_cdef_sync(&pbi->cdef_sync);

      av1_free_restoration_buffers(&pbi->common);

      av1_decoder_remove(pbi);

    }

    aom_free(frame_worker_data);

  }

  if (ctx->buffer_pool) {

    for (size_t i = 0; i < ctx->num_grain_image_frame_buffers; i++) {

      ctx->buffer_pool->release_fb_cb(ctx->buffer_pool->cb_priv,

                                      &ctx->grain_image_frame_buffers[i]);

    }

    av1_free_ref_frame_buffers(ctx->buffer_pool);

    av1_free_internal_frame_buffers(&ctx->buffer_pool->int_frame_buffers);

#if CONFIG_MULTITHREAD

    pthread_mutex_destroy(&ctx->buffer_pool->pool_mutex);

#endif

  }

  aom_free(ctx->frame_worker);

  aom_free(ctx->buffer_pool);

  assert(!ctx->img.self_allocd);

  aom_img_free(&ctx->img);

  aom_free(ctx);

  return AOM_CODEC_OK;

}

static aom_codec_err_t parse_timing_info(struct aom_read_bit_buffer *rb) {

  const uint32_t num_units_in_display_tick =

      aom_rb_read_unsigned_literal(rb, 32);

  const uint32_t time_scale = aom_rb_read_unsigned_literal(rb, 32);

  if (num_units_in_display_tick == 0 || time_scale == 0)

    return AOM_CODEC_UNSUP_BITSTREAM;

  const uint8_t equal_picture_interval = aom_rb_read_bit(rb);

  if (equal_picture_interval) {

    const uint32_t num_ticks_per_picture_minus_1 = aom_rb_read_uvlc(rb);

    if (num_ticks_per_picture_minus_1 == UINT32_MAX) {

      // num_ticks_per_picture_minus_1 cannot be (1 << 32) - 1.

      return AOM_CODEC_UNSUP_BITSTREAM;

    }

  }

  return AOM_CODEC_OK;

}

static aom_codec_err_t parse_decoder_model_info(

    struct aom_read_bit_buffer *rb, int *buffer_delay_length_minus_1) {

  *buffer_delay_length_minus_1 = aom_rb_read_literal(rb, 5);

  const uint32_t num_units_in_decoding_tick =

      aom_rb_read_unsigned_literal(rb, 32);

  const uint8_t buffer_removal_time_length_minus_1 = aom_rb_read_literal(rb, 5);

  const uint8_t frame_presentation_time_length_minus_1 =

      aom_rb_read_literal(rb, 5);

  (void)num_units_in_decoding_tick;

  (void)buffer_removal_time_length_minus_1;

  (void)frame_presentation_time_length_minus_1;

  return AOM_CODEC_OK;

}

static aom_codec_err_t parse_op_parameters_info(

    struct aom_read_bit_buffer *rb, int buffer_delay_length_minus_1) {

  const int n = buffer_delay_length_minus_1 + 1;

  const uint32_t decoder_buffer_delay = aom_rb_read_unsigned_literal(rb, n);

  const uint32_t encoder_buffer_delay = aom_rb_read_unsigned_literal(rb, n);

  const uint8_t low_delay_mode_flag = aom_rb_read_bit(rb);

  (void)decoder_buffer_delay;

  (void)encoder_buffer_delay;

  (void)low_delay_mode_flag;

  return AOM_CODEC_OK;

}

// Parses the operating points (including operating_point_idc, seq_level_idx,

// and seq_tier) and then sets si->number_spatial_layers and

// si->number_temporal_layers based on operating_point_idc[0].

static aom_codec_err_t parse_operating_points(struct aom_read_bit_buffer *rb,

                                              int is_reduced_header,

                                              aom_codec_stream_info_t *si) {

  int operating_point_idc0 = 0;

  if (is_reduced_header) {

    aom_rb_read_literal(rb, LEVEL_BITS);  // level

  } else {

    uint8_t decoder_model_info_present_flag = 0;

    int buffer_delay_length_minus_1 = 0;

    aom_codec_err_t status;

    const uint8_t timing_info_present_flag = aom_rb_read_bit(rb);

    if (timing_info_present_flag) {

      if ((status = parse_timing_info(rb)) != AOM_CODEC_OK) return status;

      decoder_model_info_present_flag = aom_rb_read_bit(rb);

      if (decoder_model_info_present_flag) {

        if ((status = parse_decoder_model_info(

                 rb, &buffer_delay_length_minus_1)) != AOM_CODEC_OK)

          return status;

      }

    }

    const uint8_t initial_display_delay_present_flag = aom_rb_read_bit(rb);

    const uint8_t operating_points_cnt_minus_1 =

        aom_rb_read_literal(rb, OP_POINTS_CNT_MINUS_1_BITS);

    for (int i = 0; i < operating_points_cnt_minus_1 + 1; i++) {

      int operating_point_idc;

      operating_point_idc = aom_rb_read_literal(rb, OP_POINTS_IDC_BITS);

      if (i == 0) operating_point_idc0 = operating_point_idc;

      int seq_level_idx = aom_rb_read_literal(rb, LEVEL_BITS);  // level

      if (seq_level_idx > 7) aom_rb_read_bit(rb);               // tier

      if (decoder_model_info_present_flag) {

        const uint8_t decoder_model_present_for_this_op = aom_rb_read_bit(rb);

        if (decoder_model_present_for_this_op) {

          if ((status = parse_op_parameters_info(

                   rb, buffer_delay_length_minus_1)) != AOM_CODEC_OK)

            return status;

        }

      }

      if (initial_display_delay_present_flag) {

        const uint8_t initial_display_delay_present_for_this_op =

            aom_rb_read_bit(rb);

        if (initial_display_delay_present_for_this_op)

          aom_rb_read_literal(rb, 4);  // initial_display_delay_minus_1

      }

    }

  }

  return aom_get_num_layers_from_operating_point_idc(

      operating_point_idc0, &si->number_spatial_layers,

      &si->number_temporal_layers);

}

static aom_codec_err_t decoder_peek_si_internal(const uint8_t *data,

                                                size_t data_sz,

                                                aom_codec_stream_info_t *si,

                                                int *is_intra_only) {

  int intra_only_flag = 0;

  int got_sequence_header = 0;

  int found_keyframe = 0;

  if (data + data_sz <= data || data_sz < 1) return AOM_CODEC_INVALID_PARAM;

  si->w = 0;

  si->h = 0;

  si->is_kf = 0;  // is_kf indicates whether the current packet contains a RAP

  ObuHeader obu_header;

  memset(&obu_header, 0, sizeof(obu_header));

  size_t payload_size = 0;

  size_t bytes_read = 0;

  uint8_t reduced_still_picture_hdr = 0;

  aom_codec_err_t status = aom_read_obu_header_and_size(

      data, data_sz, si->is_annexb, &obu_header, &payload_size, &bytes_read);

  if (status != AOM_CODEC_OK) return status;

  // If the first OBU is a temporal delimiter, skip over it and look at the next

  // OBU in the bitstream

  if (obu_header.type == OBU_TEMPORAL_DELIMITER) {

    // Skip any associated payload (there shouldn't be one, but just in case)

    if (data_sz < bytes_read + payload_size) return AOM_CODEC_CORRUPT_FRAME;

    data += bytes_read + payload_size;

    data_sz -= bytes_read + payload_size;

    status = aom_read_obu_header_and_size(

        data, data_sz, si->is_annexb, &obu_header, &payload_size, &bytes_read);

    if (status != AOM_CODEC_OK) return status;

  }

  while (1) {

    data += bytes_read;

    data_sz -= bytes_read;

    if (data_sz < payload_size) return AOM_CODEC_CORRUPT_FRAME;

    // Check that the selected OBU is a sequence header

    if (obu_header.type == OBU_SEQUENCE_HEADER) {

      // Sanity check on sequence header size

      if (data_sz < 2) return AOM_CODEC_CORRUPT_FRAME;

      // Read a few values from the sequence header payload

      struct aom_read_bit_buffer rb = { data, data + data_sz, 0, NULL, NULL };

      av1_read_profile(&rb);  // profile

      const uint8_t still_picture = aom_rb_read_bit(&rb);

      reduced_still_picture_hdr = aom_rb_read_bit(&rb);

      if (!still_picture && reduced_still_picture_hdr) {

        return AOM_CODEC_UNSUP_BITSTREAM;

      }

      status = parse_operating_points(&rb, reduced_still_picture_hdr, si);

      if (status != AOM_CODEC_OK) return status;

      int num_bits_width = aom_rb_read_literal(&rb, 4) + 1;

      int num_bits_height = aom_rb_read_literal(&rb, 4) + 1;

      int max_frame_width = aom_rb_read_literal(&rb, num_bits_width) + 1;

      int max_frame_height = aom_rb_read_literal(&rb, num_bits_height) + 1;

      si->w = max_frame_width;

      si->h = max_frame_height;

      got_sequence_header = 1;

    } else if (obu_header.type == OBU_FRAME_HEADER ||

               obu_header.type == OBU_FRAME) {

      if (got_sequence_header && reduced_still_picture_hdr) {

        found_keyframe = 1;

        break;

      } else {

        // make sure we have enough bits to get the frame type out

        if (data_sz < 1) return AOM_CODEC_CORRUPT_FRAME;

        struct aom_read_bit_buffer rb = { data, data + data_sz, 0, NULL, NULL };

        const int show_existing_frame = aom_rb_read_bit(&rb);

        if (!show_existing_frame) {

          const FRAME_TYPE frame_type = (FRAME_TYPE)aom_rb_read_literal(&rb, 2);

          if (frame_type == KEY_FRAME) {

            found_keyframe = 1;

            break;  // Stop here as no further OBUs will change the outcome.

          } else if (frame_type == INTRA_ONLY_FRAME) {

            intra_only_flag = 1;

          }

        }

      }

    }

    // skip past any unread OBU header data

    data += payload_size;

    data_sz -= payload_size;

    if (data_sz == 0) break;  // exit if we're out of OBUs

    status = aom_read_obu_header_and_size(

        data, data_sz, si->is_annexb, &obu_header, &payload_size, &bytes_read);

    if (status != AOM_CODEC_OK) return status;

  }

  if (got_sequence_header && found_keyframe) si->is_kf = 1;

  if (is_intra_only != NULL) *is_intra_only = intra_only_flag;

  return AOM_CODEC_OK;

}

static aom_codec_err_t decoder_peek_si(const uint8_t *data, size_t data_sz,

                                       aom_codec_stream_info_t *si) {

  return decoder_peek_si_internal(data, data_sz, si, NULL);

}

static aom_codec_err_t decoder_get_si(aom_codec_alg_priv_t *ctx,

                                      aom_codec_stream_info_t *si) {

  *si = ctx->si;

  return AOM_CODEC_OK;

}

static void set_error_detail(aom_codec_alg_priv_t *ctx,

                             const char *const error) {

  ctx->base.err_detail = error;

}

static aom_codec_err_t update_error_state(

    aom_codec_alg_priv_t *ctx, const struct aom_internal_error_info *error) {

  if (error->error_code)

    set_error_detail(ctx, error->has_detail ? error->detail : NULL);

  return error->error_code;

}

static void init_buffer_callbacks(aom_codec_alg_priv_t *ctx) {

  AVxWorker *const worker = ctx->frame_worker;

  FrameWorkerData *const frame_worker_data = (FrameWorkerData *)worker->data1;

  AV1Decoder *const pbi = frame_worker_data->pbi;

  AV1_COMMON *const cm = &pbi->common;

  BufferPool *const pool = cm->buffer_pool;

  cm->cur_frame = NULL;

  cm->features.byte_alignment = ctx->byte_alignment;

  pbi->skip_loop_filter = ctx->skip_loop_filter;

  pbi->skip_film_grain = ctx->skip_film_grain;

  if (ctx->get_ext_fb_cb != NULL && ctx->release_ext_fb_cb != NULL) {

    pool->get_fb_cb = ctx->get_ext_fb_cb;

    pool->release_fb_cb = ctx->release_ext_fb_cb;

    pool->cb_priv = ctx->ext_priv;

  } else {

    pool->get_fb_cb = av1_get_frame_buffer;

    pool->release_fb_cb = av1_release_frame_buffer;

    if (av1_alloc_internal_frame_buffers(&pool->int_frame_buffers))

      aom_internal_error(&pbi->error, AOM_CODEC_MEM_ERROR,

                         "Failed to initialize internal frame buffers");

    pool->cb_priv = &pool->int_frame_buffers;

  }

}

static int frame_worker_hook(void *arg1, void *arg2) {

  FrameWorkerData *const frame_worker_data = (FrameWorkerData *)arg1;

  const uint8_t *data = frame_worker_data->data;

  (void)arg2;

  int result = av1_receive_compressed_data(frame_worker_data->pbi,

                                           frame_worker_data->data_size, &data);

  frame_worker_data->data_end = data;

  if (result != 0) {

    // Check decode result in serial decode.

    frame_worker_data->pbi->need_resync = 1;

  }

  return !result;

}

static aom_codec_err_t init_decoder(aom_codec_alg_priv_t *ctx) {

  const AVxWorkerInterface *const winterface = aom_get_worker_interface();

  ctx->last_show_frame = NULL;

  ctx->need_resync = 1;

  ctx->flushed = 0;

  ctx->buffer_pool = (BufferPool *)aom_calloc(1, sizeof(BufferPool));

  if (ctx->buffer_pool == NULL) return AOM_CODEC_MEM_ERROR;

  ctx->buffer_pool->num_frame_bufs = FRAME_BUFFERS;

  ctx->buffer_pool->frame_bufs = (RefCntBuffer *)aom_calloc(

      ctx->buffer_pool->num_frame_bufs, sizeof(*ctx->buffer_pool->frame_bufs));

  if (ctx->buffer_pool->frame_bufs == NULL) {

    ctx->buffer_pool->num_frame_bufs = 0;

    aom_free(ctx->buffer_pool);

    ctx->buffer_pool = NULL;

    return AOM_CODEC_MEM_ERROR;

  }

#if CONFIG_MULTITHREAD

  if (pthread_mutex_init(&ctx->buffer_pool->pool_mutex, NULL)) {

    aom_free(ctx->buffer_pool->frame_bufs);

    ctx->buffer_pool->frame_bufs = NULL;

    ctx->buffer_pool->num_frame_bufs = 0;

    aom_free(ctx->buffer_pool);

    ctx->buffer_pool = NULL;

    set_error_detail(ctx, "Failed to allocate buffer pool mutex");

    return AOM_CODEC_MEM_ERROR;

  }

#endif

  ctx->frame_worker = (AVxWorker *)aom_malloc(sizeof(*ctx->frame_worker));

  if (ctx->frame_worker == NULL) {

    set_error_detail(ctx, "Failed to allocate frame_worker");

    return AOM_CODEC_MEM_ERROR;

  }

  AVxWorker *const worker = ctx->frame_worker;

  winterface->init(worker);

  worker->thread_name = "aom frameworker";

  worker->data1 = aom_memalign(32, sizeof(FrameWorkerData));

  if (worker->data1 == NULL) {

    winterface->end(worker);

    aom_free(worker);

    ctx->frame_worker = NULL;

    set_error_detail(ctx, "Failed to allocate frame_worker_data");

    return AOM_CODEC_MEM_ERROR;

  }

  FrameWorkerData *frame_worker_data = (FrameWorkerData *)worker->data1;

  frame_worker_data->pbi = av1_decoder_create(ctx->buffer_pool);

  if (frame_worker_data->pbi == NULL) {

    winterface->end(worker);

    aom_free(frame_worker_data);

    aom_free(worker);

    ctx->frame_worker = NULL;

    set_error_detail(ctx, "Failed to allocate frame_worker_data->pbi");

    return AOM_CODEC_MEM_ERROR;

  }

  frame_worker_data->frame_context_ready = 0;

  frame_worker_data->received_frame = 0;

  frame_worker_data->pbi->allow_lowbitdepth = ctx->cfg.allow_lowbitdepth;

  // If decoding in serial mode, FrameWorker thread could create tile worker

  // thread or loopfilter thread.

  frame_worker_data->pbi->max_threads = ctx->cfg.threads;

  frame_worker_data->pbi->inv_tile_order = ctx->invert_tile_order;

  frame_worker_data->pbi->common.tiles.large_scale = ctx->tile_mode;

  frame_worker_data->pbi->is_annexb = ctx->is_annexb;

  frame_worker_data->pbi->dec_tile_row = ctx->decode_tile_row;

  frame_worker_data->pbi->dec_tile_col = ctx->decode_tile_col;

  frame_worker_data->pbi->operating_point = ctx->operating_point;

  frame_worker_data->pbi->output_all_layers = ctx->output_all_layers;

  frame_worker_data->pbi->frame_size_limit = ctx->frame_size_limit;

  frame_worker_data->pbi->ext_tile_debug = ctx->ext_tile_debug;

  frame_worker_data->pbi->row_mt = ctx->row_mt;

  frame_worker_data->pbi->is_fwd_kf_present = 0;

  frame_worker_data->pbi->is_arf_frame_present = 0;

  worker->hook = frame_worker_hook;

  init_buffer_callbacks(ctx);

  return AOM_CODEC_OK;

}

static inline void check_resync(aom_codec_alg_priv_t *const ctx,

                                const AV1Decoder *const pbi) {

  // Clear resync flag if worker got a key frame or intra only frame.

  if (ctx->need_resync == 1 && pbi->need_resync == 0 &&

      frame_is_intra_only(&pbi->common))

    ctx->need_resync = 0;

}

static aom_codec_err_t decode_one(aom_codec_alg_priv_t *ctx,

                                  const uint8_t **data, size_t data_sz,

                                  void *user_priv) {

  const AVxWorkerInterface *const winterface = aom_get_worker_interface();

  // Determine the stream parameters. Note that we rely on peek_si to

  // validate that we have a buffer that does not wrap around the top

  // of the heap.

  if (!ctx->si.h) {

    int is_intra_only = 0;

    ctx->si.is_annexb = ctx->is_annexb;

    const aom_codec_err_t res =

        decoder_peek_si_internal(*data, data_sz, &ctx->si, &is_intra_only);

    if (res != AOM_CODEC_OK) return res;

    if (!ctx->si.is_kf && !is_intra_only) return AOM_CODEC_ERROR;

  }

  AVxWorker *const worker = ctx->frame_worker;

  FrameWorkerData *const frame_worker_data = (FrameWorkerData *)worker->data1;

  frame_worker_data->data = *data;

  frame_worker_data->data_size = data_sz;

  frame_worker_data->user_priv = user_priv;

  frame_worker_data->received_frame = 1;

  frame_worker_data->pbi->common.tiles.large_scale = ctx->tile_mode;

  frame_worker_data->pbi->dec_tile_row = ctx->decode_tile_row;

  frame_worker_data->pbi->dec_tile_col = ctx->decode_tile_col;

  frame_worker_data->pbi->ext_tile_debug = ctx->ext_tile_debug;

  frame_worker_data->pbi->row_mt = ctx->row_mt;

  frame_worker_data->pbi->ext_refs = ctx->ext_refs;

  frame_worker_data->pbi->is_annexb = ctx->is_annexb;

  worker->had_error = 0;

  winterface->execute(worker);

  // Update data pointer after decode.

  *data = frame_worker_data->data_end;

  if (worker->had_error)

    return update_error_state(ctx, &frame_worker_data->pbi->error);

  check_resync(ctx, frame_worker_data->pbi);

  return AOM_CODEC_OK;

}

static void release_pending_output_frames(aom_codec_alg_priv_t *ctx) {

  // Release any pending output frames from the previous decoder_decode or

  // decoder_inspect call. We need to do this even if the decoder is being

  // flushed or the input arguments are invalid.

  if (ctx->frame_worker) {

    BufferPool *const pool = ctx->buffer_pool;

    lock_buffer_pool(pool);

    AVxWorker *const worker = ctx->frame_worker;

    FrameWorkerData *const frame_worker_data = (FrameWorkerData *)worker->data1;

    struct AV1Decoder *pbi = frame_worker_data->pbi;

    for (size_t j = 0; j < pbi->num_output_frames; j++) {

      decrease_ref_count(pbi->output_frames[j], pool);

    }

    pbi->num_output_frames = 0;

    unlock_buffer_pool(pool);

    for (size_t j = 0; j < ctx->num_grain_image_frame_buffers; j++) {

      pool->release_fb_cb(pool->cb_priv, &ctx->grain_image_frame_buffers[j]);

      ctx->grain_image_frame_buffers[j].data = NULL;

      ctx->grain_image_frame_buffers[j].size = 0;

      ctx->grain_image_frame_buffers[j].priv = NULL;

    }

    ctx->num_grain_image_frame_buffers = 0;

  }

}

// This function enables the inspector to inspect non visible frames.

static aom_codec_err_t decoder_inspect(aom_codec_alg_priv_t *ctx,

                                       const uint8_t *data, size_t data_sz,

                                       void *user_priv) {

  aom_codec_err_t res = AOM_CODEC_OK;

  release_pending_output_frames(ctx);

  /* Sanity checks */

  /* NULL data ptr allowed if data_sz is 0 too */

  if (data == NULL && data_sz == 0) {

    ctx->flushed = 1;

    return AOM_CODEC_OK;

  }

  if (data == NULL || data_sz == 0) return AOM_CODEC_INVALID_PARAM;

  // Reset flushed when receiving a valid frame.

  ctx->flushed = 0;

  const uint8_t *data_start = data;

  const uint8_t *data_end = data + data_sz;

  uint64_t frame_size;

  if (ctx->is_annexb) {

    // read the size of this temporal unit

    size_t length_of_size;

    uint64_t temporal_unit_size;

    if (aom_uleb_decode(data_start, data_sz, &temporal_unit_size,

                        &length_of_size) != 0) {

      return AOM_CODEC_CORRUPT_FRAME;

    }

    data_start += length_of_size;

    if (temporal_unit_size > (size_t)(data_end - data_start))

      return AOM_CODEC_CORRUPT_FRAME;

    data_end = data_start + temporal_unit_size;

    // read the size of this frame unit

    if (aom_uleb_decode(data_start, (size_t)(data_end - data_start),

                        &frame_size, &length_of_size) != 0) {

      return AOM_CODEC_CORRUPT_FRAME;

    }

    data_start += length_of_size;

    if (frame_size > (size_t)(data_end - data_start))

      return AOM_CODEC_CORRUPT_FRAME;

  } else {

    frame_size = (uint64_t)(data_end - data_start);

  }

  if (ctx->frame_worker == NULL) {

    res = init_decoder(ctx);

    if (res != AOM_CODEC_OK) return res;

  }

  FrameWorkerData *const frame_worker_data =

      (FrameWorkerData *)ctx->frame_worker->data1;

  AV1Decoder *const pbi = frame_worker_data->pbi;

  AV1_COMMON *const cm = &pbi->common;

#if CONFIG_INSPECTION

  frame_worker_data->pbi->inspect_cb = ctx->inspect_cb;

  frame_worker_data->pbi->inspect_ctx = ctx->inspect_ctx;

#endif

  res = av1_receive_compressed_data(frame_worker_data->pbi, (size_t)frame_size,

                                    &data_start);

  check_resync(ctx, frame_worker_data->pbi);

  if (ctx->frame_worker->had_error)

    return update_error_state(ctx, &frame_worker_data->pbi->error);

  // Allow extra zero bytes after the frame end

  while (data_start < data_end) {

    const uint8_t marker = data_start[0];

    if (marker) break;

    ++data_start;

  }

  Av1DecodeReturn *data2 = (Av1DecodeReturn *)user_priv;

  data2->idx = -1;

  if (cm->cur_frame) {

    for (int i = 0; i < REF_FRAMES; ++i)

      if (cm->ref_frame_map[i] == cm->cur_frame) data2->idx = i;

  }

  data2->buf = data_start;

  data2->show_existing = cm->show_existing_frame;

  return res;

}

static aom_codec_err_t decoder_decode(aom_codec_alg_priv_t *ctx,

                                      const uint8_t *data, size_t data_sz,

                                      void *user_priv) {

  aom_codec_err_t res = AOM_CODEC_OK;

#if CONFIG_INSPECTION

  if (user_priv != 0) {

    return decoder_inspect(ctx, data, data_sz, user_priv);

  }

#endif

  release_pending_output_frames(ctx);

  /* Sanity checks */

  /* NULL data ptr allowed if data_sz is 0 too */

  if (data == NULL && data_sz == 0) {

    ctx->flushed = 1;

    return AOM_CODEC_OK;

  }

  if (data == NULL || data_sz == 0) return AOM_CODEC_INVALID_PARAM;

  // Reset flushed when receiving a valid frame.

  ctx->flushed = 0;

  // Initialize the decoder worker on the first frame.

  if (ctx->frame_worker == NULL) {

    res = init_decoder(ctx);

    if (res != AOM_CODEC_OK) return res;

  }

  const uint8_t *data_start = data;

  const uint8_t *data_end = data + data_sz;

  if (ctx->is_annexb) {

    // read the size of this temporal unit

    size_t length_of_size;

    uint64_t temporal_unit_size;

    if (aom_uleb_decode(data_start, data_sz, &temporal_unit_size,

                        &length_of_size) != 0) {

      return AOM_CODEC_CORRUPT_FRAME;

    }

    data_start += length_of_size;

    if (temporal_unit_size > (size_t)(data_end - data_start))

      return AOM_CODEC_CORRUPT_FRAME;

    data_end = data_start + temporal_unit_size;

  }

  // Decode in serial mode.

  while (data_start < data_end) {

    uint64_t frame_size;

    if (ctx->is_annexb) {

      // read the size of this frame unit

      size_t length_of_size;

      if (aom_uleb_decode(data_start, (size_t)(data_end - data_start),

                          &frame_size, &length_of_size) != 0) {

        return AOM_CODEC_CORRUPT_FRAME;

      }

      data_start += length_of_size;

      if (frame_size > (size_t)(data_end - data_start))

        return AOM_CODEC_CORRUPT_FRAME;

    } else {

      frame_size = (uint64_t)(data_end - data_start);

    }

    res = decode_one(ctx, &data_start, (size_t)frame_size, user_priv);

    if (res != AOM_CODEC_OK) return res;

    // Allow extra zero bytes after the frame end

    while (data_start < data_end) {

      const uint8_t marker = data_start[0];

      if (marker) break;

      ++data_start;

    }

  }

  return res;

}

typedef struct {

  BufferPool *pool;

  aom_codec_frame_buffer_t *fb;

} AllocCbParam;

static void *AllocWithGetFrameBufferCb(void *priv, size_t size) {

  AllocCbParam *param = (AllocCbParam *)priv;

  if (param->pool->get_fb_cb(param->pool->cb_priv, size, param->fb) < 0)

    return NULL;

  if (param->fb->data == NULL || param->fb->size < size) return NULL;

  return param->fb->data;

}

// If grain_params->apply_grain is false, returns img. Otherwise, adds film

// grain to img, saves the result in grain_img, and returns grain_img.

static aom_image_t *add_grain_if_needed(aom_codec_alg_priv_t *ctx,

                                        aom_image_t *img,

                                        aom_image_t *grain_img,

                                        aom_film_grain_t *grain_params) {

  if (!grain_params->apply_grain) return img;

  const int w_even = ALIGN_POWER_OF_TWO_UNSIGNED(img->d_w, 1);

  const int h_even = ALIGN_POWER_OF_TWO_UNSIGNED(img->d_h, 1);

  BufferPool *const pool = ctx->buffer_pool;

  aom_codec_frame_buffer_t *fb =

      &ctx->grain_image_frame_buffers[ctx->num_grain_image_frame_buffers];

  AllocCbParam param;

  param.pool = pool;

  param.fb = fb;

  if (!aom_img_alloc_with_cb(grain_img, img->fmt, w_even, h_even, 16,

                             AllocWithGetFrameBufferCb, &param)) {

    return NULL;

  }

  grain_img->user_priv = img->user_priv;

  grain_img->fb_priv = fb->priv;

  if (av1_add_film_grain(grain_params, img, grain_img)) {

    pool->release_fb_cb(pool->cb_priv, fb);

    return NULL;

  }

  ctx->num_grain_image_frame_buffers++;

  return grain_img;

}

// Copies and clears the metadata from AV1Decoder.

static void move_decoder_metadata_to_img(AV1Decoder *pbi, aom_image_t *img) {

  if (pbi->metadata && img) {

    assert(!img->metadata);

    img->metadata = pbi->metadata;

    pbi->metadata = NULL;

  }

}

static aom_image_t *decoder_get_frame(aom_codec_alg_priv_t *ctx,

                                      aom_codec_iter_t *iter) {

  aom_image_t *img = NULL;

  if (!iter) {

    return NULL;

  }

  // To avoid having to allocate any extra storage, treat 'iter' as

  // simply a pointer to an integer index

  uintptr_t *index = (uintptr_t *)iter;

  if (ctx->frame_worker == NULL) {

    return NULL;

  }

  const AVxWorkerInterface *const winterface = aom_get_worker_interface();

  AVxWorker *const worker = ctx->frame_worker;

  FrameWorkerData *const frame_worker_data = (FrameWorkerData *)worker->data1;

  AV1Decoder *const pbi = frame_worker_data->pbi;

  pbi->error.error_code = AOM_CODEC_OK;

  pbi->error.has_detail = 0;

  AV1_COMMON *const cm = &pbi->common;

  CommonTileParams *const tiles = &cm->tiles;

  // Wait for the frame from worker thread.

  if (!winterface->sync(worker)) {

    // Decoding failed. Release the worker thread.

    frame_worker_data->received_frame = 0;

    ctx->need_resync = 1;

    // TODO(aomedia:3519): Set an error code. Check if a different error code

    // should be used if ctx->flushed != 1.

    return NULL;

  }

  // Check if worker has received any frames.

  if (frame_worker_data->received_frame == 1) {

    frame_worker_data->received_frame = 0;

    check_resync(ctx, frame_worker_data->pbi);

  }

  YV12_BUFFER_CONFIG *sd;

  aom_film_grain_t *grain_params;

  if (av1_get_raw_frame(frame_worker_data->pbi, *index, &sd, &grain_params) !=

      0) {

    return NULL;

  }

  RefCntBuffer *const output_frame_buf = pbi->output_frames[*index];

  ctx->last_show_frame = output_frame_buf;

  if (ctx->need_resync) return NULL;

  aom_img_remove_metadata(&ctx->img);

  yuvconfig2image(&ctx->img, sd, frame_worker_data->user_priv);

  move_decoder_metadata_to_img(pbi, &ctx->img);

  if (!pbi->ext_tile_debug && tiles->large_scale) {

    *index += 1;  // Advance the iterator to point to the next image

    aom_img_remove_metadata(&ctx->img);

    yuvconfig2image(&ctx->img, &pbi->tile_list_outbuf, NULL);

    move_decoder_metadata_to_img(pbi, &ctx->img);

    img = &ctx->img;

    return img;

  }

  const int num_planes = av1_num_planes(cm);

  if (pbi->ext_tile_debug && tiles->single_tile_decoding &&

      pbi->dec_tile_row >= 0) {

    int tile_width, tile_height;

    if (!av1_get_uniform_tile_size(cm, &tile_width, &tile_height)) {

      return NULL;

    }

    const int tile_row = AOMMIN(pbi->dec_tile_row, tiles->rows - 1);

    const int mi_row = tile_row * tile_height;

    const int ssy = ctx->img.y_chroma_shift;

    int plane;

    ctx->img.planes[0] += mi_row * MI_SIZE * ctx->img.stride[0];

    if (num_planes > 1) {

      for (plane = 1; plane < MAX_MB_PLANE; ++plane) {

        ctx->img.planes[plane] +=

            mi_row * (MI_SIZE >> ssy) * ctx->img.stride[plane];

      }

    }

    ctx->img.d_h =

        AOMMIN(tile_height, cm->mi_params.mi_rows - mi_row) * MI_SIZE;

  }

  if (pbi->ext_tile_debug && tiles->single_tile_decoding &&

      pbi->dec_tile_col >= 0) {

    int tile_width, tile_height;

    if (!av1_get_uniform_tile_size(cm, &tile_width, &tile_height)) {

      return NULL;

    }

    const int tile_col = AOMMIN(pbi->dec_tile_col, tiles->cols - 1);

    const int mi_col = tile_col * tile_width;

    const int ssx = ctx->img.x_chroma_shift;

    const int is_hbd = (ctx->img.fmt & AOM_IMG_FMT_HIGHBITDEPTH) ? 1 : 0;

    int plane;

    ctx->img.planes[0] += mi_col * MI_SIZE * (1 + is_hbd);

    if (num_planes > 1) {

      for (plane = 1; plane < MAX_MB_PLANE; ++plane) {

        ctx->img.planes[plane] += mi_col * (MI_SIZE >> ssx) * (1 + is_hbd);

      }

    }

    ctx->img.d_w = AOMMIN(tile_width, cm->mi_params.mi_cols - mi_col) * MI_SIZE;

  }

  ctx->img.fb_priv = output_frame_buf->raw_frame_buffer.priv;

  img = &ctx->img;

  img->temporal_id = output_frame_buf->temporal_id;

  img->spatial_id = output_frame_buf->spatial_id;

  if (pbi->skip_film_grain) grain_params->apply_grain = 0;

  aom_image_t *res =

      add_grain_if_needed(ctx, img, &ctx->image_with_grain, grain_params);

  if (!res) {

    pbi->error.error_code = AOM_CODEC_CORRUPT_FRAME;

    pbi->error.has_detail = 1;

    snprintf(pbi->error.detail, sizeof(pbi->error.detail),

             "Grain synthesis failed\n");

    return res;

  }

  *index += 1;  // Advance the iterator to point to the next image

  return res;

}

static aom_codec_err_t decoder_set_fb_fn(

    aom_codec_alg_priv_t *ctx, aom_get_frame_buffer_cb_fn_t cb_get,

    aom_release_frame_buffer_cb_fn_t cb_release, void *cb_priv) {

  if (cb_get == NULL || cb_release == NULL) {

    return AOM_CODEC_INVALID_PARAM;

  }

  if (ctx->frame_worker != NULL) {

    // If the decoder has already been initialized, do not accept changes to

    // the frame buffer functions.

    return AOM_CODEC_ERROR;

  }

  ctx->get_ext_fb_cb = cb_get;

  ctx->release_ext_fb_cb = cb_release;

  ctx->ext_priv = cb_priv;

  return AOM_CODEC_OK;

}

static aom_codec_err_t ctrl_set_reference(aom_codec_alg_priv_t *ctx,

                                          va_list args) {

  av1_ref_frame_t *const data = va_arg(args, av1_ref_frame_t *);

  if (data) {

    av1_ref_frame_t *const frame = data;

    YV12_BUFFER_CONFIG sd;

    AVxWorker *const worker = ctx->frame_worker;

    if (worker == NULL) return AOM_CODEC_ERROR;

    FrameWorkerData *const frame_worker_data = (FrameWorkerData *)worker->data1;

    image2yuvconfig(&frame->img, &sd);

    struct aom_internal_error_info *const error =

        frame_worker_data->pbi->common.error;

    if (setjmp(error->jmp)) {

      error->setjmp = 0;

      return error->error_code;

    }

    error->setjmp = 1;

    av1_set_reference_dec(&frame_worker_data->pbi->common, frame->idx,

                          frame->use_external_ref, &sd);

    error->setjmp = 0;

    return AOM_CODEC_OK;

  } else {

    return AOM_CODEC_INVALID_PARAM;

  }

}

static aom_codec_err_t ctrl_copy_reference(aom_codec_alg_priv_t *ctx,

                                           va_list args) {

  const av1_ref_frame_t *const frame = va_arg(args, av1_ref_frame_t *);

  if (frame) {

    YV12_BUFFER_CONFIG sd;

    AVxWorker *const worker = ctx->frame_worker;

    if (worker == NULL) return AOM_CODEC_ERROR;

    FrameWorkerData *const frame_worker_data = (FrameWorkerData *)worker->data1;

    image2yuvconfig(&frame->img, &sd);

    return av1_copy_reference_dec(frame_worker_data->pbi, frame->idx, &sd);