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path: root/vp9/decoder/vp9_decoder.c
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/*
 *  Copyright (c) 2010 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.
 */

#include <assert.h>
#include <limits.h>
#include <stdio.h>

#include "./vp9_rtcd.h"
#include "./vpx_dsp_rtcd.h"
#include "./vpx_scale_rtcd.h"

#include "vpx_mem/vpx_mem.h"
#include "vpx_ports/system_state.h"
#include "vpx_ports/vpx_once.h"
#include "vpx_ports/vpx_timer.h"
#include "vpx_scale/vpx_scale.h"
#include "vpx_util/vpx_thread.h"

#include "vp9/common/vp9_alloccommon.h"
#include "vp9/common/vp9_loopfilter.h"
#include "vp9/common/vp9_onyxc_int.h"
#if CONFIG_VP9_POSTPROC
#include "vp9/common/vp9_postproc.h"
#endif
#include "vp9/common/vp9_quant_common.h"
#include "vp9/common/vp9_reconintra.h"

#include "vp9/decoder/vp9_decodeframe.h"
#include "vp9/decoder/vp9_decoder.h"
#include "vp9/decoder/vp9_detokenize.h"

static void initialize_dec(void) {
  static volatile int init_done = 0;

  if (!init_done) {
    vp9_rtcd();
    vpx_dsp_rtcd();
    vpx_scale_rtcd();
    vp9_init_intra_predictors();
    init_done = 1;
  }
}

static void vp9_dec_setup_mi(VP9_COMMON *cm) {
  cm->mi = cm->mip + cm->mi_stride + 1;
  cm->mi_grid_visible = cm->mi_grid_base + cm->mi_stride + 1;
  memset(cm->mi_grid_base, 0,
         cm->mi_stride * (cm->mi_rows + 1) * sizeof(*cm->mi_grid_base));
}

void vp9_dec_alloc_row_mt_mem(RowMTWorkerData *row_mt_worker_data,
                              VP9_COMMON *cm, int num_sbs, int max_threads,
                              int num_jobs) {
  int plane;
  const size_t dqcoeff_size = (num_sbs << DQCOEFFS_PER_SB_LOG2) *
                              sizeof(*row_mt_worker_data->dqcoeff[0]);
  row_mt_worker_data->num_jobs = num_jobs;
#if CONFIG_MULTITHREAD
  {
    int i;
    CHECK_MEM_ERROR(
        &cm->error, row_mt_worker_data->recon_sync_mutex,
        vpx_malloc(sizeof(*row_mt_worker_data->recon_sync_mutex) * num_jobs));
    if (row_mt_worker_data->recon_sync_mutex) {
      for (i = 0; i < num_jobs; ++i) {
        pthread_mutex_init(&row_mt_worker_data->recon_sync_mutex[i], NULL);
      }
    }

    CHECK_MEM_ERROR(
        &cm->error, row_mt_worker_data->recon_sync_cond,
        vpx_malloc(sizeof(*row_mt_worker_data->recon_sync_cond) * num_jobs));
    if (row_mt_worker_data->recon_sync_cond) {
      for (i = 0; i < num_jobs; ++i) {
        pthread_cond_init(&row_mt_worker_data->recon_sync_cond[i], NULL);
      }
    }
  }
#endif
  row_mt_worker_data->num_sbs = num_sbs;
  for (plane = 0; plane < 3; ++plane) {
    CHECK_MEM_ERROR(&cm->error, row_mt_worker_data->dqcoeff[plane],
                    vpx_memalign(32, dqcoeff_size));
    memset(row_mt_worker_data->dqcoeff[plane], 0, dqcoeff_size);
    CHECK_MEM_ERROR(&cm->error, row_mt_worker_data->eob[plane],
                    vpx_calloc(num_sbs << EOBS_PER_SB_LOG2,
                               sizeof(*row_mt_worker_data->eob[plane])));
  }
  CHECK_MEM_ERROR(&cm->error, row_mt_worker_data->partition,
                  vpx_calloc(num_sbs * PARTITIONS_PER_SB,
                             sizeof(*row_mt_worker_data->partition)));
  CHECK_MEM_ERROR(&cm->error, row_mt_worker_data->recon_map,
                  vpx_calloc(num_sbs, sizeof(*row_mt_worker_data->recon_map)));

  // allocate memory for thread_data
  if (row_mt_worker_data->thread_data == NULL) {
    const size_t thread_size =
        max_threads * sizeof(*row_mt_worker_data->thread_data);
    CHECK_MEM_ERROR(&cm->error, row_mt_worker_data->thread_data,
                    vpx_memalign(32, thread_size));
  }
}

void vp9_dec_free_row_mt_mem(RowMTWorkerData *row_mt_worker_data) {
  if (row_mt_worker_data != NULL) {
    int plane;
#if CONFIG_MULTITHREAD
    int i;
    if (row_mt_worker_data->recon_sync_mutex != NULL) {
      for (i = 0; i < row_mt_worker_data->num_jobs; ++i) {
        pthread_mutex_destroy(&row_mt_worker_data->recon_sync_mutex[i]);
      }
      vpx_free(row_mt_worker_data->recon_sync_mutex);
      row_mt_worker_data->recon_sync_mutex = NULL;
    }
    if (row_mt_worker_data->recon_sync_cond != NULL) {
      for (i = 0; i < row_mt_worker_data->num_jobs; ++i) {
        pthread_cond_destroy(&row_mt_worker_data->recon_sync_cond[i]);
      }
      vpx_free(row_mt_worker_data->recon_sync_cond);
      row_mt_worker_data->recon_sync_cond = NULL;
    }
#endif
    for (plane = 0; plane < 3; ++plane) {
      vpx_free(row_mt_worker_data->eob[plane]);
      row_mt_worker_data->eob[plane] = NULL;
      vpx_free(row_mt_worker_data->dqcoeff[plane]);
      row_mt_worker_data->dqcoeff[plane] = NULL;
    }
    vpx_free(row_mt_worker_data->partition);
    row_mt_worker_data->partition = NULL;
    vpx_free(row_mt_worker_data->recon_map);
    row_mt_worker_data->recon_map = NULL;
    vpx_free(row_mt_worker_data->thread_data);
    row_mt_worker_data->thread_data = NULL;
  }
}

static int vp9_dec_alloc_mi(VP9_COMMON *cm, int mi_size) {
  cm->mip = vpx_calloc(mi_size, sizeof(*cm->mip));
  if (!cm->mip) return 1;
  cm->mi_alloc_size = mi_size;
  cm->mi_grid_base = (MODE_INFO **)vpx_calloc(mi_size, sizeof(MODE_INFO *));
  if (!cm->mi_grid_base) return 1;
  return 0;
}

static void vp9_dec_free_mi(VP9_COMMON *cm) {
#if CONFIG_VP9_POSTPROC
  // MFQE allocates an additional mip and swaps it with cm->mip.
  vpx_free(cm->postproc_state.prev_mip);
  cm->postproc_state.prev_mip = NULL;
#endif
  vpx_free(cm->mip);
  cm->mip = NULL;
  vpx_free(cm->mi_grid_base);
  cm->mi_grid_base = NULL;
  cm->mi_alloc_size = 0;
}

VP9Decoder *vp9_decoder_create(BufferPool *const pool) {
  VP9Decoder *volatile const pbi = vpx_memalign(32, sizeof(*pbi));
  VP9_COMMON *volatile const cm = pbi ? &pbi->common : NULL;

  if (!cm) return NULL;

  vp9_zero(*pbi);

  if (setjmp(cm->error.jmp)) {
    cm->error.setjmp = 0;
    vp9_decoder_remove(pbi);
    return NULL;
  }

  cm->error.setjmp = 1;

  CHECK_MEM_ERROR(&cm->error, cm->fc,
                  (FRAME_CONTEXT *)vpx_calloc(1, sizeof(*cm->fc)));
  CHECK_MEM_ERROR(
      &cm->error, cm->frame_contexts,
      (FRAME_CONTEXT *)vpx_calloc(FRAME_CONTEXTS, sizeof(*cm->frame_contexts)));

  pbi->need_resync = 1;
  once(initialize_dec);

  // Initialize the references to not point to any frame buffers.
  memset(&cm->ref_frame_map, -1, sizeof(cm->ref_frame_map));
  memset(&cm->next_ref_frame_map, -1, sizeof(cm->next_ref_frame_map));

  init_frame_indexes(cm);
  pbi->ready_for_new_data = 1;
  pbi->common.buffer_pool = pool;

  cm->bit_depth = VPX_BITS_8;
  cm->dequant_bit_depth = VPX_BITS_8;

  cm->alloc_mi = vp9_dec_alloc_mi;
  cm->free_mi = vp9_dec_free_mi;
  cm->setup_mi = vp9_dec_setup_mi;

  vp9_loop_filter_init(cm);

  cm->error.setjmp = 0;

  vpx_get_worker_interface()->init(&pbi->lf_worker);

  return pbi;
}

void vp9_decoder_remove(VP9Decoder *pbi) {
  int i;

  if (!pbi) return;

  vpx_get_worker_interface()->end(&pbi->lf_worker);
  vpx_free(pbi->lf_worker.data1);

  for (i = 0; i < pbi->num_tile_workers; ++i) {
    VPxWorker *const worker = &pbi->tile_workers[i];
    vpx_get_worker_interface()->end(worker);
  }

  vpx_free(pbi->tile_worker_data);
  vpx_free(pbi->tile_workers);

  if (pbi->num_tile_workers > 0) {
    vp9_loop_filter_dealloc(&pbi->lf_row_sync);
  }

  if (pbi->row_mt == 1) {
    vp9_dec_free_row_mt_mem(pbi->row_mt_worker_data);
    if (pbi->row_mt_worker_data != NULL) {
      vp9_jobq_deinit(&pbi->row_mt_worker_data->jobq);
      vpx_free(pbi->row_mt_worker_data->jobq_buf);
#if CONFIG_MULTITHREAD
      pthread_mutex_destroy(&pbi->row_mt_worker_data->recon_done_mutex);
#endif
    }
    vpx_free(pbi->row_mt_worker_data);
  }

  vp9_remove_common(&pbi->common);
  vpx_free(pbi);
}

static int equal_dimensions(const YV12_BUFFER_CONFIG *a,
                            const YV12_BUFFER_CONFIG *b) {
  return a->y_height == b->y_height && a->y_width == b->y_width &&
         a->uv_height == b->uv_height && a->uv_width == b->uv_width;
}

vpx_codec_err_t vp9_copy_reference_dec(VP9Decoder *pbi,
                                       VP9_REFFRAME ref_frame_flag,
                                       YV12_BUFFER_CONFIG *sd) {
  VP9_COMMON *cm = &pbi->common;

  /* TODO(jkoleszar): The decoder doesn't have any real knowledge of what the
   * encoder is using the frame buffers for. This is just a stub to keep the
   * vpxenc --test-decode functionality working, and will be replaced in a
   * later commit that adds VP9-specific controls for this functionality.
   */
  if (ref_frame_flag == VP9_LAST_FLAG) {
    const YV12_BUFFER_CONFIG *const cfg = get_ref_frame(cm, 0);
    if (cfg == NULL) {
      vpx_internal_error(&cm->error, VPX_CODEC_ERROR,
                         "No 'last' reference frame");
      return VPX_CODEC_ERROR;
    }
    if (!equal_dimensions(cfg, sd))
      vpx_internal_error(&cm->error, VPX_CODEC_ERROR,
                         "Incorrect buffer dimensions");
    else
      vpx_yv12_copy_frame(cfg, sd);
  } else {
    vpx_internal_error(&cm->error, VPX_CODEC_ERROR, "Invalid reference frame");
  }

  return cm->error.error_code;
}

vpx_codec_err_t vp9_set_reference_dec(VP9_COMMON *cm,
                                      VP9_REFFRAME ref_frame_flag,
                                      YV12_BUFFER_CONFIG *sd) {
  int idx;
  YV12_BUFFER_CONFIG *ref_buf = NULL;

  // TODO(jkoleszar): The decoder doesn't have any real knowledge of what the
  // encoder is using the frame buffers for. This is just a stub to keep the
  // vpxenc --test-decode functionality working, and will be replaced in a
  // later commit that adds VP9-specific controls for this functionality.
  // (Yunqing) The set_reference control depends on the following setting in
  // encoder.
  // cpi->lst_fb_idx = 0;
  // cpi->gld_fb_idx = 1;
  // cpi->alt_fb_idx = 2;
  if (ref_frame_flag == VP9_LAST_FLAG) {
    idx = cm->ref_frame_map[0];
  } else if (ref_frame_flag == VP9_GOLD_FLAG) {
    idx = cm->ref_frame_map[1];
  } else if (ref_frame_flag == VP9_ALT_FLAG) {
    idx = cm->ref_frame_map[2];
  } else {
    vpx_internal_error(&cm->error, VPX_CODEC_ERROR, "Invalid reference frame");
    return cm->error.error_code;
  }

  if (idx < 0 || idx >= FRAME_BUFFERS) {
    vpx_internal_error(&cm->error, VPX_CODEC_ERROR,
                       "Invalid reference frame map");
    return cm->error.error_code;
  }

  // Get the destination reference buffer.
  ref_buf = &cm->buffer_pool->frame_bufs[idx].buf;

  if (!equal_dimensions(ref_buf, sd)) {
    vpx_internal_error(&cm->error, VPX_CODEC_ERROR,
                       "Incorrect buffer dimensions");
  } else {
    // Overwrite the reference frame buffer.
    vpx_yv12_copy_frame(sd, ref_buf);
  }

  return cm->error.error_code;
}

/* If any buffer updating is signaled it should be done here. */
static void swap_frame_buffers(VP9Decoder *pbi) {
  int ref_index = 0, mask;
  VP9_COMMON *const cm = &pbi->common;
  BufferPool *const pool = cm->buffer_pool;
  RefCntBuffer *const frame_bufs = cm->buffer_pool->frame_bufs;

  for (mask = pbi->refresh_frame_flags; mask; mask >>= 1) {
    const int old_idx = cm->ref_frame_map[ref_index];
    // Current thread releases the holding of reference frame.
    decrease_ref_count(old_idx, frame_bufs, pool);

    // Release the reference frame in reference map.
    if (mask & 1) {
      decrease_ref_count(old_idx, frame_bufs, pool);
    }
    cm->ref_frame_map[ref_index] = cm->next_ref_frame_map[ref_index];
    ++ref_index;
  }

  // Current thread releases the holding of reference frame.
  for (; ref_index < REF_FRAMES && !cm->show_existing_frame; ++ref_index) {
    const int old_idx = cm->ref_frame_map[ref_index];
    decrease_ref_count(old_idx, frame_bufs, pool);
    cm->ref_frame_map[ref_index] = cm->next_ref_frame_map[ref_index];
  }
  pbi->hold_ref_buf = 0;
  cm->frame_to_show = get_frame_new_buffer(cm);

  --frame_bufs[cm->new_fb_idx].ref_count;

  // Invalidate these references until the next frame starts.
  for (ref_index = 0; ref_index < 3; ref_index++)
    cm->frame_refs[ref_index].idx = -1;
}

static void release_fb_on_decoder_exit(VP9Decoder *pbi) {
  const VPxWorkerInterface *const winterface = vpx_get_worker_interface();
  VP9_COMMON *volatile const cm = &pbi->common;
  BufferPool *volatile const pool = cm->buffer_pool;
  RefCntBuffer *volatile const frame_bufs = cm->buffer_pool->frame_bufs;
  int i;

  // Synchronize all threads immediately as a subsequent decode call may
  // cause a resize invalidating some allocations.
  winterface->sync(&pbi->lf_worker);
  for (i = 0; i < pbi->num_tile_workers; ++i) {
    winterface->sync(&pbi->tile_workers[i]);
  }

  // Release all the reference buffers if worker thread is holding them.
  if (pbi->hold_ref_buf == 1) {
    int ref_index = 0, mask;
    for (mask = pbi->refresh_frame_flags; mask; mask >>= 1) {
      const int old_idx = cm->ref_frame_map[ref_index];
      // Current thread releases the holding of reference frame.
      decrease_ref_count(old_idx, frame_bufs, pool);

      // Release the reference frame in reference map.
      if (mask & 1) {
        decrease_ref_count(old_idx, frame_bufs, pool);
      }
      ++ref_index;
    }

    // Current thread releases the holding of reference frame.
    for (; ref_index < REF_FRAMES && !cm->show_existing_frame; ++ref_index) {
      const int old_idx = cm->ref_frame_map[ref_index];
      decrease_ref_count(old_idx, frame_bufs, pool);
    }
    pbi->hold_ref_buf = 0;
  }
}

int vp9_receive_compressed_data(VP9Decoder *pbi, size_t size,
                                const uint8_t **psource) {
  VP9_COMMON *volatile const cm = &pbi->common;
  BufferPool *volatile const pool = cm->buffer_pool;
  RefCntBuffer *volatile const frame_bufs = cm->buffer_pool->frame_bufs;
  const uint8_t *source = *psource;
  int retcode = 0;
  cm->error.error_code = VPX_CODEC_OK;

  if (size == 0) {
    // This is used to signal that we are missing frames.
    // We do not know if the missing frame(s) was supposed to update
    // any of the reference buffers, but we act conservative and
    // mark only the last buffer as corrupted.
    //
    // TODO(jkoleszar): Error concealment is undefined and non-normative
    // at this point, but if it becomes so, [0] may not always be the correct
    // thing to do here.
    if (cm->frame_refs[0].idx > 0) {
      assert(cm->frame_refs[0].buf != NULL);
      cm->frame_refs[0].buf->corrupted = 1;
    }
  }

  pbi->ready_for_new_data = 0;

  // Check if the previous frame was a frame without any references to it.
  if (cm->new_fb_idx >= 0 && frame_bufs[cm->new_fb_idx].ref_count == 0 &&
      !frame_bufs[cm->new_fb_idx].released) {
    pool->release_fb_cb(pool->cb_priv,
                        &frame_bufs[cm->new_fb_idx].raw_frame_buffer);
    frame_bufs[cm->new_fb_idx].released = 1;
  }

  // Find a free frame buffer. Return error if can not find any.
  cm->new_fb_idx = get_free_fb(cm);
  if (cm->new_fb_idx == INVALID_IDX) {
    pbi->ready_for_new_data = 1;
    release_fb_on_decoder_exit(pbi);
    vpx_clear_system_state();
    vpx_internal_error(&cm->error, VPX_CODEC_MEM_ERROR,
                       "Unable to find free frame buffer");
    return cm->error.error_code;
  }

  // Assign a MV array to the frame buffer.
  cm->cur_frame = &pool->frame_bufs[cm->new_fb_idx];

  pbi->hold_ref_buf = 0;
  pbi->cur_buf = &frame_bufs[cm->new_fb_idx];

  if (setjmp(cm->error.jmp)) {
    cm->error.setjmp = 0;
    pbi->ready_for_new_data = 1;
    release_fb_on_decoder_exit(pbi);
    // Release current frame.
    decrease_ref_count(cm->new_fb_idx, frame_bufs, pool);
    vpx_clear_system_state();
    return -1;
  }

  cm->error.setjmp = 1;
  vp9_decode_frame(pbi, source, source + size, psource);

  swap_frame_buffers(pbi);

  vpx_clear_system_state();

  if (!cm->show_existing_frame) {
    cm->last_show_frame = cm->show_frame;
    cm->prev_frame = cm->cur_frame;
    if (cm->seg.enabled) vp9_swap_current_and_last_seg_map(cm);
  }

  if (cm->show_frame) cm->cur_show_frame_fb_idx = cm->new_fb_idx;

  // Update progress in frame parallel decode.
  cm->last_width = cm->width;
  cm->last_height = cm->height;
  if (cm->show_frame) {
    cm->current_video_frame++;
  }

  cm->error.setjmp = 0;
  return retcode;
}

int vp9_get_raw_frame(VP9Decoder *pbi, YV12_BUFFER_CONFIG *sd,
                      vp9_ppflags_t *flags) {
  VP9_COMMON *const cm = &pbi->common;
  int ret = -1;
#if !CONFIG_VP9_POSTPROC
  (void)*flags;
#endif

  if (pbi->ready_for_new_data == 1) return ret;

  pbi->ready_for_new_data = 1;

  /* no raw frame to show!!! */
  if (!cm->show_frame) return ret;

  pbi->ready_for_new_data = 1;

#if CONFIG_VP9_POSTPROC
  if (!cm->show_existing_frame) {
    ret = vp9_post_proc_frame(cm, sd, flags, cm->width);
  } else {
    *sd = *cm->frame_to_show;
    ret = 0;
  }
#else
  *sd = *cm->frame_to_show;
  ret = 0;
#endif /*!CONFIG_POSTPROC*/
  vpx_clear_system_state();
  return ret;
}

vpx_codec_err_t vp9_parse_superframe_index(const uint8_t *data, size_t data_sz,
                                           uint32_t sizes[8], int *count,
                                           vpx_decrypt_cb decrypt_cb,
                                           void *decrypt_state) {
  // A chunk ending with a byte matching 0xc0 is an invalid chunk unless
  // it is a super frame index. If the last byte of real video compression
  // data is 0xc0 the encoder must add a 0 byte. If we have the marker but
  // not the associated matching marker byte at the front of the index we have
  // an invalid bitstream and need to return an error.

  uint8_t marker;

  assert(data_sz);
  marker = read_marker(decrypt_cb, decrypt_state, data + data_sz - 1);
  *count = 0;

  if ((marker & 0xe0) == 0xc0) {
    const uint32_t frames = (marker & 0x7) + 1;
    const uint32_t mag = ((marker >> 3) & 0x3) + 1;
    const size_t index_sz = 2 + mag * frames;

    // This chunk is marked as having a superframe index but doesn't have
    // enough data for it, thus it's an invalid superframe index.
    if (data_sz < index_sz) return VPX_CODEC_CORRUPT_FRAME;

    {
      const uint8_t marker2 =
          read_marker(decrypt_cb, decrypt_state, data + data_sz - index_sz);

      // This chunk is marked as having a superframe index but doesn't have
      // the matching marker byte at the front of the index therefore it's an
      // invalid chunk.
      if (marker != marker2) return VPX_CODEC_CORRUPT_FRAME;
    }

    {
      // Found a valid superframe index.
      uint32_t i, j;
      const uint8_t *x = &data[data_sz - index_sz + 1];

      // Frames has a maximum of 8 and mag has a maximum of 4.
      uint8_t clear_buffer[32];
      assert(sizeof(clear_buffer) >= frames * mag);
      if (decrypt_cb) {
        decrypt_cb(decrypt_state, x, clear_buffer, frames * mag);
        x = clear_buffer;
      }

      for (i = 0; i < frames; ++i) {
        uint32_t this_sz = 0;

        for (j = 0; j < mag; ++j) this_sz |= ((uint32_t)(*x++)) << (j * 8);
        sizes[i] = this_sz;
      }
      *count = frames;
    }
  }
  return VPX_CODEC_OK;
}