examples/lightfield_encoder.c - avm - Git at Google

 /*
  * Copyright (c) 2021, Alliance for Open Media. All rights reserved
  *
  * This source code is subject to the terms of the BSD 3-Clause Clear License
  * and the Alliance for Open Media Patent License 1.0. If the BSD 3-Clause Clear
  * License was not distributed with this source code in the LICENSE file, you
  * can obtain it at aomedia.org/license/software-license/bsd-3-c-c/.  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
  * aomedia.org/license/patent-license/.
  */

 // Lightfield Encoder
 // ==================
 //
 // This is an example of a simple lightfield encoder.  It builds upon the
 // twopass_encoder.c example. It takes an input file in YV12 format,
 // treating it as a planar lightfield instead of a video. The img_width
 // and img_height arguments are the dimensions of the lightfield images,
 // while the lf_width and lf_height arguments are the number of
 // lightfield images in each dimension. The lf_blocksize determines the
 // number of reference images used for MCP. For example, 5 means that there
 // is a reference image for every 5x5 lightfield image block. All images
 // within a block will use the center image in that block as the reference
 // image for MCP.
 // Run "make test" to download lightfield test data: vase10x10.yuv.
 // Run lightfield encoder to encode whole lightfield:
 // examples/lightfield_encoder 1024 1024 vase10x10.yuv vase10x10.ivf 10 10 5

 // Note: In bitstream.c and encoder.c, define EXT_TILE_DEBUG as 1 will print
 // out the uncompressed header and the frame contexts, which can be used to
 // test the bit exactness of the headers and the frame contexts for large scale
 // tile coded frames.

 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>

 #include "aom/aom_encoder.h"
 #include "aom/aomcx.h"
 #include "aom_scale/yv12config.h"
 #include "av1/common/enums.h"
 #include "common/tools_common.h"
 #include "common/video_writer.h"

 static const char *exec_name;

 void usage_exit(void) {
   fprintf(stderr,
           "Usage: %s <img_width> <img_height> <infile> <outfile> "
           "<lf_width> <lf_height> <lf_blocksize>\n",
           exec_name);
   exit(EXIT_FAILURE);
 }

 static int img_size_bytes(aom_image_t *img) {
   int image_size_bytes = 0;
   int plane;
   for (plane = 0; plane < 3; ++plane) {
     const int w = aom_img_plane_width(img, plane) *
                   ((img->fmt & AOM_IMG_FMT_HIGHBITDEPTH) ? 2 : 1);
     const int h = aom_img_plane_height(img, plane);
     image_size_bytes += w * h;
   }
   return image_size_bytes;
 }

 static int encode_frame(aom_codec_ctx_t *ctx, const aom_image_t *img,
                         aom_codec_pts_t pts, unsigned int duration,
                         aom_enc_frame_flags_t flags, AvxVideoWriter *writer) {
   int got_pkts = 0;
   aom_codec_iter_t iter = NULL;
   const aom_codec_cx_pkt_t *pkt = NULL;
   const aom_codec_err_t res = aom_codec_encode(ctx, img, pts, duration, flags);
   if (res != AOM_CODEC_OK) die_codec(ctx, "Failed to encode frame.");

   while ((pkt = aom_codec_get_cx_data(ctx, &iter)) != NULL) {
     got_pkts = 1;
     if (pkt->kind == AOM_CODEC_CX_FRAME_PKT
 #if CONFIG_OUTPUT_FRAME_BASED_ON_ORDER_HINT
         || pkt->kind == AOM_CODEC_CX_FRAME_NULL_PKT
 #endif  // CONFIG_OUTPUT_FRAME_BASED_ON_ORDER_HINT
     ) {
       const int keyframe = (pkt->data.frame.flags & AOM_FRAME_IS_KEY) != 0;

       if (!aom_video_writer_write_frame(writer, pkt->data.frame.buf,
                                         pkt->data.frame.sz,
                                         pkt->data.frame.pts))
         die_codec(ctx, "Failed to write compressed frame.");
       printf(keyframe ? "K" : ".");
       fflush(stdout);
     }
   }

   return got_pkts;
 }

 static void get_raw_image(aom_image_t **frame_to_encode, aom_image_t *raw,
                           aom_image_t *raw_shift) {
   // Need to allocate larger buffer to use hbd internal.
   int input_shift = 0;
   aom_img_upshift(raw_shift, raw, input_shift);
   *frame_to_encode = raw_shift;
 }

 static void pass1(aom_image_t *raw, FILE *infile, const char *outfile_name,
                   aom_codec_iface_t *encoder, aom_codec_enc_cfg_t *cfg,
                   int lf_width, int lf_height, int lf_blocksize, int flags,
                   aom_image_t *raw_shift) {
   AvxVideoInfo info = { get_fourcc_by_aom_encoder(encoder),
                         cfg->g_w,
                         cfg->g_h,
                         { cfg->g_timebase.num, cfg->g_timebase.den },
                         0 };
   AvxVideoWriter *writer = NULL;
   aom_codec_ctx_t codec;
   int frame_count = 0;
   int image_size_bytes = img_size_bytes(raw);
   int bu, bv;
   int u_blocks, v_blocks;
   aom_image_t *frame_to_encode;
   aom_image_t reference_images[MAX_EXTERNAL_REFERENCES];
   int reference_image_num = 0;
   int i;

   writer = aom_video_writer_open(outfile_name, kContainerIVF, &info);
   if (!writer) die("Failed to open %s for writing", outfile_name);

   if (aom_codec_enc_init(&codec, encoder, cfg, flags))
     die("Failed to initialize encoder");
   if (aom_codec_control(&codec, AOME_SET_ENABLEAUTOALTREF, 0))
     die_codec(&codec, "Failed to turn off auto altref");
   if (aom_codec_control(&codec, AV1E_SET_FRAME_PARALLEL_DECODING, 0))
     die_codec(&codec, "Failed to set frame parallel decoding");
   if (aom_codec_control(&codec, AV1E_ENABLE_EXT_TILE_DEBUG, 1))
     die_codec(&codec, "Failed to enable encoder ext_tile debug");
   if (aom_codec_control(&codec, AOME_SET_CPUUSED, 3))
     die_codec(&codec, "Failed to set cpu-used");

   // Note: The superblock is a sequence parameter and has to be the same for 1
   // sequence. In lightfield application, must choose the superblock size(either
   // 64x64 or 128x128) before the encoding starts. Otherwise, the default is
   // AOM_SUPERBLOCK_SIZE_DYNAMIC, and the superblock size will be set to 64x64
   // internally.
   if (aom_codec_control(&codec, AV1E_SET_SUPERBLOCK_SIZE,
                         AOM_SUPERBLOCK_SIZE_64X64))
     die_codec(&codec, "Failed to set SB size");

   u_blocks = (lf_width + lf_blocksize - 1) / lf_blocksize;
   v_blocks = (lf_height + lf_blocksize - 1) / lf_blocksize;

   reference_image_num = u_blocks * v_blocks;
   // Set the max gf group length so the references are guaranteed to be in
   // a different gf group than any of the regular frames. This avoids using
   // both vbr and constant quality mode in a single group. The number of
   // references now cannot surpass 17 because of the enforced MAX_GF_INTERVAL of
   // 16. If it is necessary to exceed this reference frame limit, one will have
   // to do some additional handling to ensure references are in separate gf
   // groups from the regular frames.
   if (aom_codec_control(&codec, AV1E_SET_MAX_GF_INTERVAL,
                         reference_image_num - 1))
     die_codec(&codec, "Failed to set max gf interval");
   aom_img_fmt_t ref_fmt = AOM_IMG_FMT_I420;
   ref_fmt |= AOM_IMG_FMT_HIGHBITDEPTH;
   // Allocate memory with the border so that it can be used as a reference.
   int border_in_pixels =
       (codec.config.enc->rc_resize_mode || codec.config.enc->rc_superres_mode)
           ? AOM_BORDER_IN_PIXELS
           : AOM_ENC_NO_SCALE_BORDER;
   for (i = 0; i < reference_image_num; i++) {
     if (!aom_img_alloc_with_border(&reference_images[i], ref_fmt, cfg->g_w,
                                    cfg->g_h, 32, 8, border_in_pixels)) {
       die("Failed to allocate image.");
     }
   }

   printf("\n Second pass: ");

   // Encode reference images first.
   printf("Encoding Reference Images\n");
   for (bv = 0; bv < v_blocks; ++bv) {
     for (bu = 0; bu < u_blocks; ++bu) {
       const int block_u_min = bu * lf_blocksize;
       const int block_v_min = bv * lf_blocksize;
       int block_u_end = (bu + 1) * lf_blocksize;
       int block_v_end = (bv + 1) * lf_blocksize;
       int u_block_size, v_block_size;
       int block_ref_u, block_ref_v;

       block_u_end = block_u_end < lf_width ? block_u_end : lf_width;
       block_v_end = block_v_end < lf_height ? block_v_end : lf_height;
       u_block_size = block_u_end - block_u_min;
       v_block_size = block_v_end - block_v_min;
       block_ref_u = block_u_min + u_block_size / 2;
       block_ref_v = block_v_min + v_block_size / 2;

       printf("A%d, ", (block_ref_u + block_ref_v * lf_width));
       fseek(infile, (block_ref_u + block_ref_v * lf_width) * image_size_bytes,
             SEEK_SET);
       aom_img_read(raw, infile);

       get_raw_image(&frame_to_encode, raw, raw_shift);

       // Reference frames may be encoded without tiles.
       ++frame_count;
       printf("Encoding reference image %d of %d\n", bv * u_blocks + bu,
              u_blocks * v_blocks);
       encode_frame(&codec, frame_to_encode, frame_count, 1,
                    AOM_EFLAG_NO_REF_LAST2 | AOM_EFLAG_NO_REF_LAST3 |
                        AOM_EFLAG_NO_REF_GF | AOM_EFLAG_NO_REF_ARF |
                        AOM_EFLAG_NO_REF_BWD | AOM_EFLAG_NO_REF_ARF2 |
                        AOM_EFLAG_NO_UPD_ALL | AOM_EFLAG_NO_UPD_ENTROPY,
                    writer);

       if (aom_codec_control(&codec, AV1_COPY_NEW_FRAME_IMAGE,
                             &reference_images[frame_count - 1]))
         die_codec(&codec, "Failed to copy decoder reference frame");
     }
   }

   cfg->large_scale_tile = 1;
   // Fixed q encoding for camera frames.
   cfg->rc_end_usage = AOM_Q;
   if (aom_codec_enc_config_set(&codec, cfg))
     die_codec(&codec, "Failed to configure encoder");

   // The fixed q value used in encoding.
   if (aom_codec_control(&codec, AOME_SET_QP, 36))
     die_codec(&codec, "Failed to set cq level");
   if (aom_codec_control(&codec, AV1E_SET_FRAME_PARALLEL_DECODING, 1))
     die_codec(&codec, "Failed to set frame parallel decoding");
   if (aom_codec_control(&codec, AV1E_SET_SINGLE_TILE_DECODING, 1))
     die_codec(&codec, "Failed to turn on single tile decoding");
   // Set tile_columns and tile_rows to MAX values, which guarantees the tile
   // size of 64 x 64 pixels(i.e. 1 SB) for <= 4k resolution.
   if (aom_codec_control(&codec, AV1E_SET_TILE_COLUMNS, 6))
     die_codec(&codec, "Failed to set tile width");
   if (aom_codec_control(&codec, AV1E_SET_TILE_ROWS, 6))
     die_codec(&codec, "Failed to set tile height");

   for (bv = 0; bv < v_blocks; ++bv) {
     for (bu = 0; bu < u_blocks; ++bu) {
       const int block_u_min = bu * lf_blocksize;
       const int block_v_min = bv * lf_blocksize;
       int block_u_end = (bu + 1) * lf_blocksize;
       int block_v_end = (bv + 1) * lf_blocksize;
       int u, v;
       block_u_end = block_u_end < lf_width ? block_u_end : lf_width;
       block_v_end = block_v_end < lf_height ? block_v_end : lf_height;
       for (v = block_v_min; v < block_v_end; ++v) {
         for (u = block_u_min; u < block_u_end; ++u) {
           av1_ref_frame_t ref;
           ref.idx = 0;
           ref.use_external_ref = 1;
           ref.img = reference_images[bv * u_blocks + bu];
           if (aom_codec_control(&codec, AV1_SET_REFERENCE, &ref))
             die_codec(&codec, "Failed to set reference frame");

           printf("C%d, ", (u + v * lf_width));
           fseek(infile, (u + v * lf_width) * image_size_bytes, SEEK_SET);
           aom_img_read(raw, infile);
           get_raw_image(&frame_to_encode, raw, raw_shift);

           ++frame_count;
           printf("Encoding image %d of %d\n",
                  frame_count - (u_blocks * v_blocks), lf_width * lf_height);
           encode_frame(&codec, frame_to_encode, frame_count, 1,
                        AOM_EFLAG_NO_REF_LAST2 | AOM_EFLAG_NO_REF_LAST3 |
                            AOM_EFLAG_NO_REF_GF | AOM_EFLAG_NO_REF_ARF |
                            AOM_EFLAG_NO_REF_BWD | AOM_EFLAG_NO_REF_ARF2 |
                            AOM_EFLAG_NO_UPD_ALL | AOM_EFLAG_NO_UPD_ENTROPY,
                        writer);
         }
       }
     }
   }

   // Flush encoder.
   // No ARF, this should not be needed.
   while (encode_frame(&codec, NULL, -1, 1, 0, writer)) {
   }

   for (i = 0; i < reference_image_num; i++) aom_img_free(&reference_images[i]);

   if (aom_codec_destroy(&codec)) die_codec(&codec, "Failed to destroy codec.");

   // Modify large_scale_file fourcc.
   if (cfg->large_scale_tile == 1)
     aom_video_writer_set_fourcc(writer, LST_FOURCC);
   aom_video_writer_close(writer);

   printf("\nSecond pass complete. Processed %d frames.\n", frame_count);
 }

 int main(int argc, char **argv) {
   FILE *infile = NULL;
   int w, h;
   // The number of lightfield images in the u and v dimensions.
   int lf_width, lf_height;
   // Defines how many images refer to the same reference image for MCP.
   // lf_blocksize X lf_blocksize images will all use the reference image
   // in the middle of the block of images.
   int lf_blocksize;
   aom_codec_ctx_t codec;
   aom_codec_enc_cfg_t cfg;
   aom_image_t raw;
   aom_image_t raw_shift;
   aom_codec_err_t res;
   int flags = 0;

   const int fps = 30;
   const int bitrate = 200;  // kbit/s
   const char *const width_arg = argv[1];
   const char *const height_arg = argv[2];
   const char *const infile_arg = argv[3];
   const char *const outfile_arg = argv[4];
   const char *const lf_width_arg = argv[5];
   const char *const lf_height_arg = argv[6];
   const char *lf_blocksize_arg = argv[7];
   exec_name = argv[0];

   if (argc < 8) die("Invalid number of arguments");

   aom_codec_iface_t *encoder = get_aom_encoder_by_short_name("av1");
   if (!encoder) die("Unsupported codec.");

   w = (int)strtol(width_arg, NULL, 0);
   h = (int)strtol(height_arg, NULL, 0);
   lf_width = (int)strtol(lf_width_arg, NULL, 0);
   lf_height = (int)strtol(lf_height_arg, NULL, 0);
   lf_blocksize = (int)strtol(lf_blocksize_arg, NULL, 0);
   lf_blocksize = lf_blocksize < lf_width ? lf_blocksize : lf_width;
   lf_blocksize = lf_blocksize < lf_height ? lf_blocksize : lf_height;

   if (w <= 0 || h <= 0 || (w % 2) != 0 || (h % 2) != 0)
     die("Invalid frame size: %dx%d", w, h);
   if (lf_width <= 0 || lf_height <= 0)
     die("Invalid lf_width and/or lf_height: %dx%d", lf_width, lf_height);
   if (lf_blocksize <= 0) die("Invalid lf_blocksize: %d", lf_blocksize);

   if (!aom_img_alloc(&raw, AOM_IMG_FMT_I420, w, h, 32)) {
     die("Failed to allocate image.");
   }
   // Need to allocate larger buffer to use hbd internal.
   aom_img_alloc(&raw_shift, AOM_IMG_FMT_I420 | AOM_IMG_FMT_HIGHBITDEPTH, w, h,
                 32);

   printf("Using %s\n", aom_codec_iface_name(encoder));

   // Configuration
   res = aom_codec_enc_config_default(encoder, &cfg, 0);
   if (res) die_codec(&codec, "Failed to get default codec config.");

   cfg.g_w = w;
   cfg.g_h = h;
   cfg.g_timebase.num = 1;
   cfg.g_timebase.den = fps;
   cfg.rc_target_bitrate = bitrate;
   cfg.g_error_resilient = 0;  // This is required.
   cfg.g_lag_in_frames = 0;    // need to set this since default is 19.
   cfg.kf_mode = AOM_KF_DISABLED;
   cfg.large_scale_tile = 0;  // Only set it to 1 for camera frame encoding.
   cfg.g_bit_depth = AOM_BITS_8;

   if (!(infile = fopen(infile_arg, "rb")))
     die("Failed to open %s for reading", infile_arg);

   // Pass 1
   cfg.g_pass = AOM_RC_ONE_PASS;
   pass1(&raw, infile, outfile_arg, encoder, &cfg, lf_width, lf_height,
         lf_blocksize, flags, &raw_shift);

   aom_img_free(&raw_shift);
   aom_img_free(&raw);
   fclose(infile);

   return EXIT_SUCCESS;
 }
	/*
	* Copyright (c) 2021, Alliance for Open Media. All rights reserved
	*
	* This source code is subject to the terms of the BSD 3-Clause Clear License
	* and the Alliance for Open Media Patent License 1.0. If the BSD 3-Clause Clear
	* License was not distributed with this source code in the LICENSE file, you
	* can obtain it at aomedia.org/license/software-license/bsd-3-c-c/. 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
	* aomedia.org/license/patent-license/.
	*/

	// Lightfield Encoder
	// ==================
	//
	// This is an example of a simple lightfield encoder. It builds upon the
	// twopass_encoder.c example. It takes an input file in YV12 format,
	// treating it as a planar lightfield instead of a video. The img_width
	// and img_height arguments are the dimensions of the lightfield images,
	// while the lf_width and lf_height arguments are the number of
	// lightfield images in each dimension. The lf_blocksize determines the
	// number of reference images used for MCP. For example, 5 means that there
	// is a reference image for every 5x5 lightfield image block. All images
	// within a block will use the center image in that block as the reference
	// image for MCP.
	// Run "make test" to download lightfield test data: vase10x10.yuv.
	// Run lightfield encoder to encode whole lightfield:
	// examples/lightfield_encoder 1024 1024 vase10x10.yuv vase10x10.ivf 10 10 5

	// Note: In bitstream.c and encoder.c, define EXT_TILE_DEBUG as 1 will print
	// out the uncompressed header and the frame contexts, which can be used to
	// test the bit exactness of the headers and the frame contexts for large scale
	// tile coded frames.

	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>

	#include "aom/aom_encoder.h"
	#include "aom/aomcx.h"
	#include "aom_scale/yv12config.h"
	#include "av1/common/enums.h"
	#include "common/tools_common.h"
	#include "common/video_writer.h"

	static const char *exec_name;

	void usage_exit(void) {
	fprintf(stderr,
	"Usage: %s <img_width> <img_height> <infile> <outfile> "
	"<lf_width> <lf_height> <lf_blocksize>\n",
	exec_name);
	exit(EXIT_FAILURE);
	}

	static int img_size_bytes(aom_image_t *img) {
	int image_size_bytes = 0;
	int plane;
	for (plane = 0; plane < 3; ++plane) {
	const int w = aom_img_plane_width(img, plane) *
	((img->fmt & AOM_IMG_FMT_HIGHBITDEPTH) ? 2 : 1);
	const int h = aom_img_plane_height(img, plane);
	image_size_bytes += w * h;
	}
	return image_size_bytes;
	}

	static int encode_frame(aom_codec_ctx_t ctx, const aom_image_t img,
	aom_codec_pts_t pts, unsigned int duration,
	aom_enc_frame_flags_t flags, AvxVideoWriter *writer) {
	int got_pkts = 0;
	aom_codec_iter_t iter = NULL;
	const aom_codec_cx_pkt_t *pkt = NULL;
	const aom_codec_err_t res = aom_codec_encode(ctx, img, pts, duration, flags);
	if (res != AOM_CODEC_OK) die_codec(ctx, "Failed to encode frame.");

	while ((pkt = aom_codec_get_cx_data(ctx, &iter)) != NULL) {
	got_pkts = 1;
	if (pkt->kind == AOM_CODEC_CX_FRAME_PKT
	#if CONFIG_OUTPUT_FRAME_BASED_ON_ORDER_HINT
	\|\| pkt->kind == AOM_CODEC_CX_FRAME_NULL_PKT
	#endif // CONFIG_OUTPUT_FRAME_BASED_ON_ORDER_HINT
	) {
	const int keyframe = (pkt->data.frame.flags & AOM_FRAME_IS_KEY) != 0;

	if (!aom_video_writer_write_frame(writer, pkt->data.frame.buf,
	pkt->data.frame.sz,
	pkt->data.frame.pts))
	die_codec(ctx, "Failed to write compressed frame.");
	printf(keyframe ? "K" : ".");
	fflush(stdout);
	}
	}

	return got_pkts;
	}

	static void get_raw_image(aom_image_t *frame_to_encode, aom_image_t raw,
	aom_image_t *raw_shift) {
	// Need to allocate larger buffer to use hbd internal.
	int input_shift = 0;
	aom_img_upshift(raw_shift, raw, input_shift);
	*frame_to_encode = raw_shift;
	}

	static void pass1(aom_image_t raw, FILE infile, const char *outfile_name,
	aom_codec_iface_t encoder, aom_codec_enc_cfg_t cfg,
	int lf_width, int lf_height, int lf_blocksize, int flags,
	aom_image_t *raw_shift) {
	AvxVideoInfo info = { get_fourcc_by_aom_encoder(encoder),
	cfg->g_w,
	cfg->g_h,
	{ cfg->g_timebase.num, cfg->g_timebase.den },
	0 };
	AvxVideoWriter *writer = NULL;
	aom_codec_ctx_t codec;
	int frame_count = 0;
	int image_size_bytes = img_size_bytes(raw);
	int bu, bv;
	int u_blocks, v_blocks;
	aom_image_t *frame_to_encode;
	aom_image_t reference_images[MAX_EXTERNAL_REFERENCES];
	int reference_image_num = 0;
	int i;

	writer = aom_video_writer_open(outfile_name, kContainerIVF, &info);
	if (!writer) die("Failed to open %s for writing", outfile_name);

	if (aom_codec_enc_init(&codec, encoder, cfg, flags))
	die("Failed to initialize encoder");
	if (aom_codec_control(&codec, AOME_SET_ENABLEAUTOALTREF, 0))
	die_codec(&codec, "Failed to turn off auto altref");
	if (aom_codec_control(&codec, AV1E_SET_FRAME_PARALLEL_DECODING, 0))
	die_codec(&codec, "Failed to set frame parallel decoding");
	if (aom_codec_control(&codec, AV1E_ENABLE_EXT_TILE_DEBUG, 1))
	die_codec(&codec, "Failed to enable encoder ext_tile debug");
	if (aom_codec_control(&codec, AOME_SET_CPUUSED, 3))
	die_codec(&codec, "Failed to set cpu-used");

	// Note: The superblock is a sequence parameter and has to be the same for 1
	// sequence. In lightfield application, must choose the superblock size(either
	// 64x64 or 128x128) before the encoding starts. Otherwise, the default is
	// AOM_SUPERBLOCK_SIZE_DYNAMIC, and the superblock size will be set to 64x64
	// internally.
	if (aom_codec_control(&codec, AV1E_SET_SUPERBLOCK_SIZE,
	AOM_SUPERBLOCK_SIZE_64X64))
	die_codec(&codec, "Failed to set SB size");

	u_blocks = (lf_width + lf_blocksize - 1) / lf_blocksize;
	v_blocks = (lf_height + lf_blocksize - 1) / lf_blocksize;

	reference_image_num = u_blocks * v_blocks;
	// Set the max gf group length so the references are guaranteed to be in
	// a different gf group than any of the regular frames. This avoids using
	// both vbr and constant quality mode in a single group. The number of
	// references now cannot surpass 17 because of the enforced MAX_GF_INTERVAL of
	// 16. If it is necessary to exceed this reference frame limit, one will have
	// to do some additional handling to ensure references are in separate gf
	// groups from the regular frames.
	if (aom_codec_control(&codec, AV1E_SET_MAX_GF_INTERVAL,
	reference_image_num - 1))
	die_codec(&codec, "Failed to set max gf interval");
	aom_img_fmt_t ref_fmt = AOM_IMG_FMT_I420;
	ref_fmt \|= AOM_IMG_FMT_HIGHBITDEPTH;
	// Allocate memory with the border so that it can be used as a reference.
	int border_in_pixels =
	(codec.config.enc->rc_resize_mode \|\| codec.config.enc->rc_superres_mode)
	? AOM_BORDER_IN_PIXELS
	: AOM_ENC_NO_SCALE_BORDER;
	for (i = 0; i < reference_image_num; i++) {
	if (!aom_img_alloc_with_border(&reference_images[i], ref_fmt, cfg->g_w,
	cfg->g_h, 32, 8, border_in_pixels)) {
	die("Failed to allocate image.");
	}
	}

	printf("\n Second pass: ");

	// Encode reference images first.
	printf("Encoding Reference Images\n");
	for (bv = 0; bv < v_blocks; ++bv) {
	for (bu = 0; bu < u_blocks; ++bu) {
	const int block_u_min = bu * lf_blocksize;
	const int block_v_min = bv * lf_blocksize;
	int block_u_end = (bu + 1) * lf_blocksize;
	int block_v_end = (bv + 1) * lf_blocksize;
	int u_block_size, v_block_size;
	int block_ref_u, block_ref_v;

	block_u_end = block_u_end < lf_width ? block_u_end : lf_width;
	block_v_end = block_v_end < lf_height ? block_v_end : lf_height;
	u_block_size = block_u_end - block_u_min;
	v_block_size = block_v_end - block_v_min;
	block_ref_u = block_u_min + u_block_size / 2;
	block_ref_v = block_v_min + v_block_size / 2;

	printf("A%d, ", (block_ref_u + block_ref_v * lf_width));
	fseek(infile, (block_ref_u + block_ref_v * lf_width) * image_size_bytes,
	SEEK_SET);
	aom_img_read(raw, infile);

	get_raw_image(&frame_to_encode, raw, raw_shift);

	// Reference frames may be encoded without tiles.
	++frame_count;
	printf("Encoding reference image %d of %d\n", bv * u_blocks + bu,
	u_blocks * v_blocks);
	encode_frame(&codec, frame_to_encode, frame_count, 1,
	AOM_EFLAG_NO_REF_LAST2 \| AOM_EFLAG_NO_REF_LAST3 \|
	AOM_EFLAG_NO_REF_GF \| AOM_EFLAG_NO_REF_ARF \|
	AOM_EFLAG_NO_REF_BWD \| AOM_EFLAG_NO_REF_ARF2 \|
	AOM_EFLAG_NO_UPD_ALL \| AOM_EFLAG_NO_UPD_ENTROPY,
	writer);

	if (aom_codec_control(&codec, AV1_COPY_NEW_FRAME_IMAGE,
	&reference_images[frame_count - 1]))
	die_codec(&codec, "Failed to copy decoder reference frame");
	}
	}

	cfg->large_scale_tile = 1;
	// Fixed q encoding for camera frames.
	cfg->rc_end_usage = AOM_Q;
	if (aom_codec_enc_config_set(&codec, cfg))
	die_codec(&codec, "Failed to configure encoder");

	// The fixed q value used in encoding.
	if (aom_codec_control(&codec, AOME_SET_QP, 36))
	die_codec(&codec, "Failed to set cq level");
	if (aom_codec_control(&codec, AV1E_SET_FRAME_PARALLEL_DECODING, 1))
	die_codec(&codec, "Failed to set frame parallel decoding");
	if (aom_codec_control(&codec, AV1E_SET_SINGLE_TILE_DECODING, 1))
	die_codec(&codec, "Failed to turn on single tile decoding");
	// Set tile_columns and tile_rows to MAX values, which guarantees the tile
	// size of 64 x 64 pixels(i.e. 1 SB) for <= 4k resolution.
	if (aom_codec_control(&codec, AV1E_SET_TILE_COLUMNS, 6))
	die_codec(&codec, "Failed to set tile width");
	if (aom_codec_control(&codec, AV1E_SET_TILE_ROWS, 6))
	die_codec(&codec, "Failed to set tile height");

	for (bv = 0; bv < v_blocks; ++bv) {
	for (bu = 0; bu < u_blocks; ++bu) {
	const int block_u_min = bu * lf_blocksize;
	const int block_v_min = bv * lf_blocksize;
	int block_u_end = (bu + 1) * lf_blocksize;
	int block_v_end = (bv + 1) * lf_blocksize;
	int u, v;
	block_u_end = block_u_end < lf_width ? block_u_end : lf_width;
	block_v_end = block_v_end < lf_height ? block_v_end : lf_height;
	for (v = block_v_min; v < block_v_end; ++v) {
	for (u = block_u_min; u < block_u_end; ++u) {
	av1_ref_frame_t ref;
	ref.idx = 0;
	ref.use_external_ref = 1;
	ref.img = reference_images[bv * u_blocks + bu];
	if (aom_codec_control(&codec, AV1_SET_REFERENCE, &ref))
	die_codec(&codec, "Failed to set reference frame");

	printf("C%d, ", (u + v * lf_width));
	fseek(infile, (u + v * lf_width) * image_size_bytes, SEEK_SET);
	aom_img_read(raw, infile);
	get_raw_image(&frame_to_encode, raw, raw_shift);

	++frame_count;
	printf("Encoding image %d of %d\n",
	frame_count - (u_blocks * v_blocks), lf_width * lf_height);
	encode_frame(&codec, frame_to_encode, frame_count, 1,
	AOM_EFLAG_NO_REF_LAST2 \| AOM_EFLAG_NO_REF_LAST3 \|
	AOM_EFLAG_NO_REF_GF \| AOM_EFLAG_NO_REF_ARF \|
	AOM_EFLAG_NO_REF_BWD \| AOM_EFLAG_NO_REF_ARF2 \|
	AOM_EFLAG_NO_UPD_ALL \| AOM_EFLAG_NO_UPD_ENTROPY,
	writer);
	}
	}
	}
	}

	// Flush encoder.
	// No ARF, this should not be needed.
	while (encode_frame(&codec, NULL, -1, 1, 0, writer)) {
	}

	for (i = 0; i < reference_image_num; i++) aom_img_free(&reference_images[i]);

	if (aom_codec_destroy(&codec)) die_codec(&codec, "Failed to destroy codec.");

	// Modify large_scale_file fourcc.
	if (cfg->large_scale_tile == 1)
	aom_video_writer_set_fourcc(writer, LST_FOURCC);
	aom_video_writer_close(writer);

	printf("\nSecond pass complete. Processed %d frames.\n", frame_count);
	}

	int main(int argc, char **argv) {
	FILE *infile = NULL;
	int w, h;
	// The number of lightfield images in the u and v dimensions.
	int lf_width, lf_height;
	// Defines how many images refer to the same reference image for MCP.
	// lf_blocksize X lf_blocksize images will all use the reference image
	// in the middle of the block of images.
	int lf_blocksize;
	aom_codec_ctx_t codec;
	aom_codec_enc_cfg_t cfg;
	aom_image_t raw;
	aom_image_t raw_shift;
	aom_codec_err_t res;
	int flags = 0;

	const int fps = 30;
	const int bitrate = 200; // kbit/s
	const char *const width_arg = argv[1];
	const char *const height_arg = argv[2];
	const char *const infile_arg = argv[3];
	const char *const outfile_arg = argv[4];
	const char *const lf_width_arg = argv[5];
	const char *const lf_height_arg = argv[6];
	const char *lf_blocksize_arg = argv[7];
	exec_name = argv[0];

	if (argc < 8) die("Invalid number of arguments");

	aom_codec_iface_t *encoder = get_aom_encoder_by_short_name("av1");
	if (!encoder) die("Unsupported codec.");

	w = (int)strtol(width_arg, NULL, 0);
	h = (int)strtol(height_arg, NULL, 0);
	lf_width = (int)strtol(lf_width_arg, NULL, 0);
	lf_height = (int)strtol(lf_height_arg, NULL, 0);
	lf_blocksize = (int)strtol(lf_blocksize_arg, NULL, 0);
	lf_blocksize = lf_blocksize < lf_width ? lf_blocksize : lf_width;
	lf_blocksize = lf_blocksize < lf_height ? lf_blocksize : lf_height;

	if (w <= 0 \|\| h <= 0 \|\| (w % 2) != 0 \|\| (h % 2) != 0)
	die("Invalid frame size: %dx%d", w, h);
	if (lf_width <= 0 \|\| lf_height <= 0)
	die("Invalid lf_width and/or lf_height: %dx%d", lf_width, lf_height);
	if (lf_blocksize <= 0) die("Invalid lf_blocksize: %d", lf_blocksize);

	if (!aom_img_alloc(&raw, AOM_IMG_FMT_I420, w, h, 32)) {
	die("Failed to allocate image.");
	}
	// Need to allocate larger buffer to use hbd internal.
	aom_img_alloc(&raw_shift, AOM_IMG_FMT_I420 \| AOM_IMG_FMT_HIGHBITDEPTH, w, h,
	32);

	printf("Using %s\n", aom_codec_iface_name(encoder));

	// Configuration
	res = aom_codec_enc_config_default(encoder, &cfg, 0);
	if (res) die_codec(&codec, "Failed to get default codec config.");

	cfg.g_w = w;
	cfg.g_h = h;
	cfg.g_timebase.num = 1;
	cfg.g_timebase.den = fps;
	cfg.rc_target_bitrate = bitrate;
	cfg.g_error_resilient = 0; // This is required.
	cfg.g_lag_in_frames = 0; // need to set this since default is 19.
	cfg.kf_mode = AOM_KF_DISABLED;
	cfg.large_scale_tile = 0; // Only set it to 1 for camera frame encoding.
	cfg.g_bit_depth = AOM_BITS_8;

	if (!(infile = fopen(infile_arg, "rb")))
	die("Failed to open %s for reading", infile_arg);

	// Pass 1
	cfg.g_pass = AOM_RC_ONE_PASS;
	pass1(&raw, infile, outfile_arg, encoder, &cfg, lf_width, lf_height,
	lf_blocksize, flags, &raw_shift);

	aom_img_free(&raw_shift);
	aom_img_free(&raw);
	fclose(infile);

	return EXIT_SUCCESS;
	}