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authortrav90 <travawine@palemoon.org>2018-10-15 21:45:30 -0500
committertrav90 <travawine@palemoon.org>2018-10-15 21:45:30 -0500
commit68569dee1416593955c1570d638b3d9250b33012 (patch)
treed960f017cd7eba3f125b7e8a813789ee2e076310 /third_party/aom/av1/decoder/decoder.c
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Import aom library
This is the reference implementation for the Alliance for Open Media's av1 video code. The commit used was 4d668d7feb1f8abd809d1bca0418570a7f142a36.
Diffstat (limited to 'third_party/aom/av1/decoder/decoder.c')
-rw-r--r--third_party/aom/av1/decoder/decoder.c583
1 files changed, 583 insertions, 0 deletions
diff --git a/third_party/aom/av1/decoder/decoder.c b/third_party/aom/av1/decoder/decoder.c
new file mode 100644
index 000000000..1bd91086e
--- /dev/null
+++ b/third_party/aom/av1/decoder/decoder.c
@@ -0,0 +1,583 @@
+/*
+ * 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 <assert.h>
+#include <limits.h>
+#include <stdio.h>
+
+#include "./av1_rtcd.h"
+#include "./aom_dsp_rtcd.h"
+#include "./aom_scale_rtcd.h"
+
+#include "aom_mem/aom_mem.h"
+#include "aom_ports/system_state.h"
+#include "aom_ports/aom_once.h"
+#include "aom_ports/aom_timer.h"
+#include "aom_scale/aom_scale.h"
+#include "aom_util/aom_thread.h"
+
+#include "av1/common/alloccommon.h"
+#include "av1/common/av1_loopfilter.h"
+#include "av1/common/onyxc_int.h"
+#include "av1/common/quant_common.h"
+#include "av1/common/reconinter.h"
+#include "av1/common/reconintra.h"
+
+#include "av1/decoder/decodeframe.h"
+#include "av1/decoder/decoder.h"
+
+#if !CONFIG_PVQ
+#include "av1/decoder/detokenize.h"
+#endif
+
+static void initialize_dec(void) {
+ static volatile int init_done = 0;
+
+ if (!init_done) {
+ av1_rtcd();
+ aom_dsp_rtcd();
+ aom_scale_rtcd();
+ av1_init_intra_predictors();
+#if CONFIG_EXT_INTER
+ av1_init_wedge_masks();
+#endif // CONFIG_EXT_INTER
+ init_done = 1;
+#if CONFIG_EC_MULTISYMBOL
+ av1_indices_from_tree(av1_intra_mode_ind, av1_intra_mode_inv,
+ av1_intra_mode_tree);
+ av1_indices_from_tree(av1_switchable_interp_ind, av1_switchable_interp_inv,
+ av1_switchable_interp_tree);
+#if CONFIG_EXT_TX
+ int s;
+ for (s = 1; s < EXT_TX_SETS_INTRA; ++s)
+ av1_indices_from_tree(av1_ext_tx_intra_ind[s], av1_ext_tx_intra_inv[s],
+ av1_ext_tx_intra_tree[s]);
+ for (s = 1; s < EXT_TX_SETS_INTER; ++s)
+ av1_indices_from_tree(av1_ext_tx_inter_ind[s], av1_ext_tx_inter_inv[s],
+ av1_ext_tx_inter_tree[s]);
+#else
+ av1_indices_from_tree(av1_ext_tx_ind, av1_ext_tx_inv, av1_ext_tx_tree);
+#endif
+ av1_indices_from_tree(av1_inter_mode_ind, av1_inter_mode_inv,
+ av1_inter_mode_tree);
+#endif
+ }
+}
+
+static void av1_dec_setup_mi(AV1_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));
+}
+
+static int av1_dec_alloc_mi(AV1_COMMON *cm, int mi_size) {
+ cm->mip = aom_calloc(mi_size, sizeof(*cm->mip));
+ if (!cm->mip) return 1;
+ cm->mi_alloc_size = mi_size;
+ cm->mi_grid_base = (MODE_INFO **)aom_calloc(mi_size, sizeof(MODE_INFO *));
+ if (!cm->mi_grid_base) return 1;
+ return 0;
+}
+
+static void av1_dec_free_mi(AV1_COMMON *cm) {
+ aom_free(cm->mip);
+ cm->mip = NULL;
+ aom_free(cm->mi_grid_base);
+ cm->mi_grid_base = NULL;
+}
+
+AV1Decoder *av1_decoder_create(BufferPool *const pool) {
+ AV1Decoder *volatile const pbi = aom_memalign(32, sizeof(*pbi));
+ AV1_COMMON *volatile const cm = pbi ? &pbi->common : NULL;
+
+ if (!cm) return NULL;
+
+ av1_zero(*pbi);
+
+ if (setjmp(cm->error.jmp)) {
+ cm->error.setjmp = 0;
+ av1_decoder_remove(pbi);
+ return NULL;
+ }
+
+ cm->error.setjmp = 1;
+
+ CHECK_MEM_ERROR(cm, cm->fc,
+ (FRAME_CONTEXT *)aom_memalign(32, sizeof(*cm->fc)));
+ CHECK_MEM_ERROR(cm, cm->frame_contexts,
+ (FRAME_CONTEXT *)aom_memalign(
+ 32, FRAME_CONTEXTS * sizeof(*cm->frame_contexts)));
+ memset(cm->fc, 0, sizeof(*cm->fc));
+ memset(cm->frame_contexts, 0, 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));
+
+ cm->current_video_frame = 0;
+ pbi->ready_for_new_data = 1;
+ pbi->common.buffer_pool = pool;
+
+ cm->bit_depth = AOM_BITS_8;
+ cm->dequant_bit_depth = AOM_BITS_8;
+
+ cm->alloc_mi = av1_dec_alloc_mi;
+ cm->free_mi = av1_dec_free_mi;
+ cm->setup_mi = av1_dec_setup_mi;
+
+ av1_loop_filter_init(cm);
+
+#if CONFIG_AOM_QM
+ aom_qm_init(cm);
+#endif
+#if CONFIG_LOOP_RESTORATION
+ av1_loop_restoration_precal();
+#endif // CONFIG_LOOP_RESTORATION
+#if CONFIG_ACCOUNTING
+ pbi->acct_enabled = 1;
+ aom_accounting_init(&pbi->accounting);
+#endif
+
+ cm->error.setjmp = 0;
+
+ aom_get_worker_interface()->init(&pbi->lf_worker);
+
+ return pbi;
+}
+
+void av1_decoder_remove(AV1Decoder *pbi) {
+ int i;
+
+ if (!pbi) return;
+
+ aom_get_worker_interface()->end(&pbi->lf_worker);
+ aom_free(pbi->lf_worker.data1);
+ aom_free(pbi->tile_data);
+ for (i = 0; i < pbi->num_tile_workers; ++i) {
+ AVxWorker *const worker = &pbi->tile_workers[i];
+ aom_get_worker_interface()->end(worker);
+ }
+ aom_free(pbi->tile_worker_data);
+ aom_free(pbi->tile_worker_info);
+ aom_free(pbi->tile_workers);
+
+ if (pbi->num_tile_workers > 0) {
+ av1_loop_filter_dealloc(&pbi->lf_row_sync);
+ }
+
+#if CONFIG_ACCOUNTING
+ aom_accounting_clear(&pbi->accounting);
+#endif
+
+ aom_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;
+}
+
+aom_codec_err_t av1_copy_reference_dec(AV1Decoder *pbi,
+ AOM_REFFRAME ref_frame_flag,
+ YV12_BUFFER_CONFIG *sd) {
+ AV1_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
+ * aomenc --test-decode functionality working, and will be replaced in a
+ * later commit that adds AV1-specific controls for this functionality.
+ */
+ if (ref_frame_flag == AOM_LAST_FLAG) {
+ const YV12_BUFFER_CONFIG *const cfg = get_ref_frame(cm, 0);
+ if (cfg == NULL) {
+ aom_internal_error(&cm->error, AOM_CODEC_ERROR,
+ "No 'last' reference frame");
+ return AOM_CODEC_ERROR;
+ }
+ if (!equal_dimensions(cfg, sd))
+ aom_internal_error(&cm->error, AOM_CODEC_ERROR,
+ "Incorrect buffer dimensions");
+ else
+ aom_yv12_copy_frame(cfg, sd);
+ } else {
+ aom_internal_error(&cm->error, AOM_CODEC_ERROR, "Invalid reference frame");
+ }
+
+ return cm->error.error_code;
+}
+
+aom_codec_err_t av1_set_reference_dec(AV1_COMMON *cm,
+ AOM_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
+ // aomenc --test-decode functionality working, and will be replaced in a
+ // later commit that adds AV1-specific controls for this functionality.
+
+ // (Yunqing) The set_reference control depends on the following setting in
+ // encoder.
+ // cpi->lst_fb_idx = 0;
+ // #if CONFIG_EXT_REFS
+ // cpi->lst2_fb_idx = 1;
+ // cpi->lst3_fb_idx = 2;
+ // cpi->gld_fb_idx = 3;
+ // cpi->bwd_fb_idx = 4;
+ // cpi->alt_fb_idx = 5;
+ // #else // CONFIG_EXT_REFS
+ // cpi->gld_fb_idx = 1;
+ // cpi->alt_fb_idx = 2;
+ // #endif // CONFIG_EXT_REFS
+
+ // TODO(zoeliu): To revisit following code and reconsider what assumption we
+ // may take on the reference frame buffer virtual indexes
+ if (ref_frame_flag == AOM_LAST_FLAG) {
+ idx = cm->ref_frame_map[0];
+#if CONFIG_EXT_REFS
+ } else if (ref_frame_flag == AOM_LAST2_FLAG) {
+ idx = cm->ref_frame_map[1];
+ } else if (ref_frame_flag == AOM_LAST3_FLAG) {
+ idx = cm->ref_frame_map[2];
+ } else if (ref_frame_flag == AOM_GOLD_FLAG) {
+ idx = cm->ref_frame_map[3];
+ } else if (ref_frame_flag == AOM_BWD_FLAG) {
+ idx = cm->ref_frame_map[4];
+ } else if (ref_frame_flag == AOM_ALT_FLAG) {
+ idx = cm->ref_frame_map[5];
+#else
+ } else if (ref_frame_flag == AOM_GOLD_FLAG) {
+ idx = cm->ref_frame_map[1];
+ } else if (ref_frame_flag == AOM_ALT_FLAG) {
+ idx = cm->ref_frame_map[2];
+#endif // CONFIG_EXT_REFS
+ } else {
+ aom_internal_error(&cm->error, AOM_CODEC_ERROR, "Invalid reference frame");
+ return cm->error.error_code;
+ }
+
+ if (idx < 0 || idx >= FRAME_BUFFERS) {
+ aom_internal_error(&cm->error, AOM_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)) {
+ aom_internal_error(&cm->error, AOM_CODEC_ERROR,
+ "Incorrect buffer dimensions");
+ } else {
+ // Overwrite the reference frame buffer.
+ aom_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(AV1Decoder *pbi) {
+ int ref_index = 0, mask;
+ AV1_COMMON *const cm = &pbi->common;
+ BufferPool *const pool = cm->buffer_pool;
+ RefCntBuffer *const frame_bufs = cm->buffer_pool->frame_bufs;
+
+ lock_buffer_pool(pool);
+ 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 holding in the reference map for the decoding
+ // of the next frame.
+ 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];
+ }
+
+ unlock_buffer_pool(pool);
+ pbi->hold_ref_buf = 0;
+ cm->frame_to_show = get_frame_new_buffer(cm);
+
+ // TODO(zoeliu): To fix the ref frame buffer update for the scenario of
+ // cm->frame_parellel_decode == 1
+ if (!cm->frame_parallel_decode || !cm->show_frame) {
+ lock_buffer_pool(pool);
+ --frame_bufs[cm->new_fb_idx].ref_count;
+ unlock_buffer_pool(pool);
+ }
+
+ // Invalidate these references until the next frame starts.
+ for (ref_index = 0; ref_index < INTER_REFS_PER_FRAME; ref_index++) {
+ cm->frame_refs[ref_index].idx = INVALID_IDX;
+ cm->frame_refs[ref_index].buf = NULL;
+ }
+}
+
+int av1_receive_compressed_data(AV1Decoder *pbi, size_t size,
+ const uint8_t **psource) {
+ AV1_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 = AOM_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;
+
+ // Find a free buffer for the new frame, releasing the reference previously
+ // held.
+
+ // Check if the previous frame was a frame without any references to it.
+ // Release frame buffer if not decoding in frame parallel mode.
+ if (!cm->frame_parallel_decode && cm->new_fb_idx >= 0 &&
+ frame_bufs[cm->new_fb_idx].ref_count == 0)
+ pool->release_fb_cb(pool->cb_priv,
+ &frame_bufs[cm->new_fb_idx].raw_frame_buffer);
+
+ // 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) return AOM_CODEC_MEM_ERROR;
+
+ // Assign a MV array to the frame buffer.
+ cm->cur_frame = &pool->frame_bufs[cm->new_fb_idx];
+
+ pbi->hold_ref_buf = 0;
+ if (cm->frame_parallel_decode) {
+ AVxWorker *const worker = pbi->frame_worker_owner;
+ av1_frameworker_lock_stats(worker);
+ frame_bufs[cm->new_fb_idx].frame_worker_owner = worker;
+ // Reset decoding progress.
+ pbi->cur_buf = &frame_bufs[cm->new_fb_idx];
+ pbi->cur_buf->row = -1;
+ pbi->cur_buf->col = -1;
+ av1_frameworker_unlock_stats(worker);
+ } else {
+ pbi->cur_buf = &frame_bufs[cm->new_fb_idx];
+ }
+
+ if (setjmp(cm->error.jmp)) {
+ const AVxWorkerInterface *const winterface = aom_get_worker_interface();
+ int i;
+
+ cm->error.setjmp = 0;
+ pbi->ready_for_new_data = 1;
+
+ // 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]);
+ }
+
+ lock_buffer_pool(pool);
+ // 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 holding in the reference map for the
+ // decoding of the next frame.
+ 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;
+ }
+ // Release current frame.
+ decrease_ref_count(cm->new_fb_idx, frame_bufs, pool);
+ unlock_buffer_pool(pool);
+
+ aom_clear_system_state();
+ return -1;
+ }
+
+ cm->error.setjmp = 1;
+ av1_decode_frame(pbi, source, source + size, psource);
+
+ swap_frame_buffers(pbi);
+
+#if CONFIG_EXT_TILE
+ // For now, we only extend the frame borders when the whole frame is decoded.
+ // Later, if needed, extend the border for the decoded tile on the frame
+ // border.
+ if (pbi->dec_tile_row == -1 && pbi->dec_tile_col == -1)
+#endif // CONFIG_EXT_TILE
+ aom_extend_frame_inner_borders(cm->frame_to_show);
+
+ aom_clear_system_state();
+
+ if (!cm->show_existing_frame) {
+ cm->last_show_frame = cm->show_frame;
+
+#if CONFIG_EXT_REFS
+ // NOTE: It is not supposed to ref to any frame not used as reference
+ if (cm->is_reference_frame)
+#endif // CONFIG_EXT_REFS
+ cm->prev_frame = cm->cur_frame;
+
+ if (cm->seg.enabled && !cm->frame_parallel_decode)
+ av1_swap_current_and_last_seg_map(cm);
+ }
+
+ // Update progress in frame parallel decode.
+ if (cm->frame_parallel_decode) {
+ // Need to lock the mutex here as another thread may
+ // be accessing this buffer.
+ AVxWorker *const worker = pbi->frame_worker_owner;
+ FrameWorkerData *const frame_worker_data = worker->data1;
+ av1_frameworker_lock_stats(worker);
+
+ if (cm->show_frame) {
+ cm->current_video_frame++;
+ }
+ frame_worker_data->frame_decoded = 1;
+ frame_worker_data->frame_context_ready = 1;
+ av1_frameworker_signal_stats(worker);
+ av1_frameworker_unlock_stats(worker);
+ } else {
+ 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 av1_get_raw_frame(AV1Decoder *pbi, YV12_BUFFER_CONFIG *sd) {
+ AV1_COMMON *const cm = &pbi->common;
+ int ret = -1;
+ 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;
+ *sd = *cm->frame_to_show;
+ ret = 0;
+ aom_clear_system_state();
+ return ret;
+}
+
+int av1_get_frame_to_show(AV1Decoder *pbi, YV12_BUFFER_CONFIG *frame) {
+ AV1_COMMON *const cm = &pbi->common;
+
+ if (!cm->show_frame || !cm->frame_to_show) return -1;
+
+ *frame = *cm->frame_to_show;
+ return 0;
+}
+
+aom_codec_err_t av1_parse_superframe_index(const uint8_t *data, size_t data_sz,
+ uint32_t sizes[8], int *count,
+ aom_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;
+ size_t frame_sz_sum = 0;
+
+ 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 - 1);
+
+ // 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 AOM_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 AOM_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[28];
+ assert(sizeof(clear_buffer) >= (frames - 1) * mag);
+ if (decrypt_cb) {
+ decrypt_cb(decrypt_state, x, clear_buffer, (frames - 1) * mag);
+ x = clear_buffer;
+ }
+
+ for (i = 0; i < frames - 1; ++i) {
+ uint32_t this_sz = 0;
+
+ for (j = 0; j < mag; ++j) this_sz |= (*x++) << (j * 8);
+ this_sz += 1;
+ sizes[i] = this_sz;
+ frame_sz_sum += this_sz;
+ }
+ sizes[i] = (uint32_t)(data_sz - index_sz - frame_sz_sum);
+ *count = frames;
+ }
+ }
+ return AOM_CODEC_OK;
+}