common/tools_common.c - aom - Git at Google

 /*
  * 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 <math.h>
 #include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>

 #include "common/tools_common.h"

 #if CONFIG_AV1_ENCODER
 #include "aom/aomcx.h"
 #endif

 #if CONFIG_AV1_DECODER
 #include "aom/aomdx.h"
 #endif

 #if defined(_WIN32) || defined(__OS2__)
 #include <io.h>
 #include <fcntl.h>

 #ifdef __OS2__
 #define _setmode setmode
 #define _fileno fileno
 #define _O_BINARY O_BINARY
 #endif
 #endif

 #define LOG_ERROR(label)               \
   do {                                 \
     const char *l = label;             \
     va_list ap;                        \
     va_start(ap, fmt);                 \
     if (l) fprintf(stderr, "%s: ", l); \
     vfprintf(stderr, fmt, ap);         \
     fprintf(stderr, "\n");             \
     va_end(ap);                        \
   } while (0)

 FILE *set_binary_mode(FILE *stream) {
   (void)stream;
 #if defined(_WIN32) || defined(__OS2__)
   _setmode(_fileno(stream), _O_BINARY);
 #endif
   return stream;
 }

 void die(const char *fmt, ...) {
   LOG_ERROR(NULL);
   usage_exit();
 }

 void fatal(const char *fmt, ...) {
   LOG_ERROR("Fatal");
   exit(EXIT_FAILURE);
 }

 void aom_tools_warn(const char *fmt, ...) { LOG_ERROR("Warning"); }

 void die_codec(aom_codec_ctx_t *ctx, const char *s) {
   const char *detail = aom_codec_error_detail(ctx);

   printf("%s: %s\n", s, aom_codec_error(ctx));
   if (detail) printf("    %s\n", detail);
   exit(EXIT_FAILURE);
 }

 int read_yuv_frame(struct AvxInputContext *input_ctx, aom_image_t *yuv_frame) {
   FILE *f = input_ctx->file;
   struct FileTypeDetectionBuffer *detect = &input_ctx->detect;
   int plane = 0;
   int shortread = 0;
   const int bytespp = (yuv_frame->fmt & AOM_IMG_FMT_HIGHBITDEPTH) ? 2 : 1;

   for (plane = 0; plane < 3; ++plane) {
     uint8_t *ptr;
     const int w = aom_img_plane_width(yuv_frame, plane);
     const int h = aom_img_plane_height(yuv_frame, plane);
     int r;

     /* Determine the correct plane based on the image format. The for-loop
      * always counts in Y,U,V order, but this may not match the order of
      * the data on disk.
      */
     switch (plane) {
       case 1:
         ptr =
             yuv_frame->planes[yuv_frame->fmt == AOM_IMG_FMT_YV12 ? AOM_PLANE_V
                                                                  : AOM_PLANE_U];
         break;
       case 2:
         ptr =
             yuv_frame->planes[yuv_frame->fmt == AOM_IMG_FMT_YV12 ? AOM_PLANE_U
                                                                  : AOM_PLANE_V];
         break;
       default: ptr = yuv_frame->planes[plane];
     }

     for (r = 0; r < h; ++r) {
       size_t needed = w * bytespp;
       size_t buf_position = 0;
       const size_t left = detect->buf_read - detect->position;
       if (left > 0) {
         const size_t more = (left < needed) ? left : needed;
         memcpy(ptr, detect->buf + detect->position, more);
         buf_position = more;
         needed -= more;
         detect->position += more;
       }
       if (needed > 0) {
         shortread |= (fread(ptr + buf_position, 1, needed, f) < needed);
       }

       ptr += yuv_frame->stride[plane];
     }
   }

   return shortread;
 }

 struct CodecInfo {
   // Pointer to a function of zero arguments that returns an aom_codec_iface_t.
   aom_codec_iface_t *(*const interface)();
   char *short_name;
   uint32_t fourcc;
 };

 #if CONFIG_AV1_ENCODER
 static const struct CodecInfo aom_encoders[] = {
   { &aom_codec_av1_cx, "av1", AV1_FOURCC },
 };

 int get_aom_encoder_count(void) {
   return sizeof(aom_encoders) / sizeof(aom_encoders[0]);
 }

 aom_codec_iface_t *get_aom_encoder_by_index(int i) {
   assert(i >= 0 && i < get_aom_encoder_count());
   return aom_encoders[i].interface();
 }

 aom_codec_iface_t *get_aom_encoder_by_short_name(const char *name) {
   for (int i = 0; i < get_aom_encoder_count(); ++i) {
     const struct CodecInfo *info = &aom_encoders[i];
     if (strcmp(info->short_name, name) == 0) return info->interface();
   }
   return NULL;
 }

 uint32_t get_fourcc_by_aom_encoder(aom_codec_iface_t *iface) {
   for (int i = 0; i < get_aom_encoder_count(); ++i) {
     const struct CodecInfo *info = &aom_encoders[i];
     if (info->interface() == iface) {
       return info->fourcc;
     }
   }
   return 0;
 }

 const char *get_short_name_by_aom_encoder(aom_codec_iface_t *iface) {
   for (int i = 0; i < get_aom_encoder_count(); ++i) {
     const struct CodecInfo *info = &aom_encoders[i];
     if (info->interface() == iface) {
       return info->short_name;
     }
   }
   return NULL;
 }

 #endif  // CONFIG_AV1_ENCODER

 #if CONFIG_AV1_DECODER
 static const struct CodecInfo aom_decoders[] = {
   { &aom_codec_av1_dx, "av1", AV1_FOURCC },
 };

 int get_aom_decoder_count(void) {
   return sizeof(aom_decoders) / sizeof(aom_decoders[0]);
 }

 aom_codec_iface_t *get_aom_decoder_by_index(int i) {
   assert(i >= 0 && i < get_aom_decoder_count());
   return aom_decoders[i].interface();
 }

 aom_codec_iface_t *get_aom_decoder_by_short_name(const char *name) {
   for (int i = 0; i < get_aom_decoder_count(); ++i) {
     const struct CodecInfo *info = &aom_decoders[i];
     if (strcmp(info->short_name, name) == 0) return info->interface();
   }
   return NULL;
 }

 aom_codec_iface_t *get_aom_decoder_by_fourcc(uint32_t fourcc) {
   for (int i = 0; i < get_aom_decoder_count(); ++i) {
     const struct CodecInfo *info = &aom_decoders[i];
     if (info->fourcc == fourcc) return info->interface();
   }
   return NULL;
 }

 const char *get_short_name_by_aom_decoder(aom_codec_iface_t *iface) {
   for (int i = 0; i < get_aom_decoder_count(); ++i) {
     const struct CodecInfo *info = &aom_decoders[i];
     if (info->interface() == iface) {
       return info->short_name;
     }
   }
   return NULL;
 }

 uint32_t get_fourcc_by_aom_decoder(aom_codec_iface_t *iface) {
   for (int i = 0; i < get_aom_decoder_count(); ++i) {
     const struct CodecInfo *info = &aom_decoders[i];
     if (info->interface() == iface) {
       return info->fourcc;
     }
   }
   return 0;
 }

 #endif  // CONFIG_AV1_DECODER

 void aom_img_write(const aom_image_t *img, FILE *file) {
   int plane;

   for (plane = 0; plane < 3; ++plane) {
     const unsigned char *buf = img->planes[plane];
     const int stride = img->stride[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);
     int y;

     for (y = 0; y < h; ++y) {
       fwrite(buf, 1, w, file);
       buf += stride;
     }
   }
 }

 int aom_img_read(aom_image_t *img, FILE *file) {
   int plane;

   for (plane = 0; plane < 3; ++plane) {
     unsigned char *buf = img->planes[plane];
     const int stride = img->stride[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);
     int y;

     for (y = 0; y < h; ++y) {
       if (fread(buf, 1, w, file) != (size_t)w) return 0;
       buf += stride;
     }
   }

   return 1;
 }

 // TODO(dkovalev) change sse_to_psnr signature: double -> int64_t
 double sse_to_psnr(double samples, double peak, double sse) {
   static const double kMaxPSNR = 100.0;

   if (sse > 0.0) {
     const double psnr = 10.0 * log10(samples * peak * peak / sse);
     return psnr > kMaxPSNR ? kMaxPSNR : psnr;
   } else {
     return kMaxPSNR;
   }
 }

 // TODO(debargha): Consolidate the functions below into a separate file.
 static void highbd_img_upshift(aom_image_t *dst, const aom_image_t *src,
                                int input_shift) {
   // Note the offset is 1 less than half.
   const int offset = input_shift > 0 ? (1 << (input_shift - 1)) - 1 : 0;
   int plane;
   if (dst->d_w != src->d_w || dst->d_h != src->d_h ||
       dst->x_chroma_shift != src->x_chroma_shift ||
       dst->y_chroma_shift != src->y_chroma_shift || dst->fmt != src->fmt ||
       input_shift < 0) {
     fatal("Unsupported image conversion");
   }
   switch (src->fmt) {
     case AOM_IMG_FMT_I42016:
     case AOM_IMG_FMT_I42216:
     case AOM_IMG_FMT_I44416: break;
     default: fatal("Unsupported image conversion"); break;
   }
   for (plane = 0; plane < 3; plane++) {
     int w = src->d_w;
     int h = src->d_h;
     int x, y;
     if (plane) {
       w = (w + src->x_chroma_shift) >> src->x_chroma_shift;
       h = (h + src->y_chroma_shift) >> src->y_chroma_shift;
     }
     for (y = 0; y < h; y++) {
       const uint16_t *p_src =
           (const uint16_t *)(src->planes[plane] + y * src->stride[plane]);
       uint16_t *p_dst =
           (uint16_t *)(dst->planes[plane] + y * dst->stride[plane]);
       for (x = 0; x < w; x++) *p_dst++ = (*p_src++ << input_shift) + offset;
     }
   }
 }

 static void lowbd_img_upshift(aom_image_t *dst, const aom_image_t *src,
                               int input_shift) {
   // Note the offset is 1 less than half.
   const int offset = input_shift > 0 ? (1 << (input_shift - 1)) - 1 : 0;
   int plane;
   if (dst->d_w != src->d_w || dst->d_h != src->d_h ||
       dst->x_chroma_shift != src->x_chroma_shift ||
       dst->y_chroma_shift != src->y_chroma_shift ||
       dst->fmt != src->fmt + AOM_IMG_FMT_HIGHBITDEPTH || input_shift < 0) {
     fatal("Unsupported image conversion");
   }
   switch (src->fmt) {
     case AOM_IMG_FMT_YV12:
     case AOM_IMG_FMT_I420:
     case AOM_IMG_FMT_I422:
     case AOM_IMG_FMT_I444: break;
     default: fatal("Unsupported image conversion"); break;
   }
   for (plane = 0; plane < 3; plane++) {
     int w = src->d_w;
     int h = src->d_h;
     int x, y;
     if (plane) {
       w = (w + src->x_chroma_shift) >> src->x_chroma_shift;
       h = (h + src->y_chroma_shift) >> src->y_chroma_shift;
     }
     for (y = 0; y < h; y++) {
       const uint8_t *p_src = src->planes[plane] + y * src->stride[plane];
       uint16_t *p_dst =
           (uint16_t *)(dst->planes[plane] + y * dst->stride[plane]);
       for (x = 0; x < w; x++) {
         *p_dst++ = (*p_src++ << input_shift) + offset;
       }
     }
   }
 }

 void aom_img_upshift(aom_image_t *dst, const aom_image_t *src,
                      int input_shift) {
   if (src->fmt & AOM_IMG_FMT_HIGHBITDEPTH) {
     highbd_img_upshift(dst, src, input_shift);
   } else {
     lowbd_img_upshift(dst, src, input_shift);
   }
 }

 void aom_img_truncate_16_to_8(aom_image_t *dst, const aom_image_t *src) {
   int plane;
   if (dst->fmt + AOM_IMG_FMT_HIGHBITDEPTH != src->fmt || dst->d_w != src->d_w ||
       dst->d_h != src->d_h || dst->x_chroma_shift != src->x_chroma_shift ||
       dst->y_chroma_shift != src->y_chroma_shift) {
     fatal("Unsupported image conversion");
   }
   switch (dst->fmt) {
     case AOM_IMG_FMT_I420:
     case AOM_IMG_FMT_I422:
     case AOM_IMG_FMT_I444: break;
     default: fatal("Unsupported image conversion"); break;
   }
   for (plane = 0; plane < 3; plane++) {
     int w = src->d_w;
     int h = src->d_h;
     int x, y;
     if (plane) {
       w = (w + src->x_chroma_shift) >> src->x_chroma_shift;
       h = (h + src->y_chroma_shift) >> src->y_chroma_shift;
     }
     for (y = 0; y < h; y++) {
       const uint16_t *p_src =
           (const uint16_t *)(src->planes[plane] + y * src->stride[plane]);
       uint8_t *p_dst = dst->planes[plane] + y * dst->stride[plane];
       for (x = 0; x < w; x++) {
         *p_dst++ = (uint8_t)(*p_src++);
       }
     }
   }
 }

 static void highbd_img_downshift(aom_image_t *dst, const aom_image_t *src,
                                  int down_shift) {
   int plane;
   if (dst->d_w != src->d_w || dst->d_h != src->d_h ||
       dst->x_chroma_shift != src->x_chroma_shift ||
       dst->y_chroma_shift != src->y_chroma_shift || dst->fmt != src->fmt ||
       down_shift < 0) {
     fatal("Unsupported image conversion");
   }
   switch (src->fmt) {
     case AOM_IMG_FMT_I42016:
     case AOM_IMG_FMT_I42216:
     case AOM_IMG_FMT_I44416: break;
     default: fatal("Unsupported image conversion"); break;
   }
   for (plane = 0; plane < 3; plane++) {
     int w = src->d_w;
     int h = src->d_h;
     int x, y;
     if (plane) {
       w = (w + src->x_chroma_shift) >> src->x_chroma_shift;
       h = (h + src->y_chroma_shift) >> src->y_chroma_shift;
     }
     for (y = 0; y < h; y++) {
       const uint16_t *p_src =
           (const uint16_t *)(src->planes[plane] + y * src->stride[plane]);
       uint16_t *p_dst =
           (uint16_t *)(dst->planes[plane] + y * dst->stride[plane]);
       for (x = 0; x < w; x++) *p_dst++ = *p_src++ >> down_shift;
     }
   }
 }

 static void lowbd_img_downshift(aom_image_t *dst, const aom_image_t *src,
                                 int down_shift) {
   int plane;
   if (dst->d_w != src->d_w || dst->d_h != src->d_h ||
       dst->x_chroma_shift != src->x_chroma_shift ||
       dst->y_chroma_shift != src->y_chroma_shift ||
       src->fmt != dst->fmt + AOM_IMG_FMT_HIGHBITDEPTH || down_shift < 0) {
     fatal("Unsupported image conversion");
   }
   switch (dst->fmt) {
     case AOM_IMG_FMT_I420:
     case AOM_IMG_FMT_I422:
     case AOM_IMG_FMT_I444: break;
     default: fatal("Unsupported image conversion"); break;
   }
   for (plane = 0; plane < 3; plane++) {
     int w = src->d_w;
     int h = src->d_h;
     int x, y;
     if (plane) {
       w = (w + src->x_chroma_shift) >> src->x_chroma_shift;
       h = (h + src->y_chroma_shift) >> src->y_chroma_shift;
     }
     for (y = 0; y < h; y++) {
       const uint16_t *p_src =
           (const uint16_t *)(src->planes[plane] + y * src->stride[plane]);
       uint8_t *p_dst = dst->planes[plane] + y * dst->stride[plane];
       for (x = 0; x < w; x++) {
         *p_dst++ = *p_src++ >> down_shift;
       }
     }
   }
 }

 void aom_img_downshift(aom_image_t *dst, const aom_image_t *src,
                        int down_shift) {
   if (dst->fmt & AOM_IMG_FMT_HIGHBITDEPTH) {
     highbd_img_downshift(dst, src, down_shift);
   } else {
     lowbd_img_downshift(dst, src, down_shift);
   }
 }

 static int img_shifted_realloc_required(const aom_image_t *img,
                                         const aom_image_t *shifted,
                                         aom_img_fmt_t required_fmt) {
   return img->d_w != shifted->d_w || img->d_h != shifted->d_h ||
          required_fmt != shifted->fmt;
 }

 void aom_shift_img(unsigned int output_bit_depth, aom_image_t **img_ptr,
                    aom_image_t **img_shifted_ptr) {
   aom_image_t *img = *img_ptr;
   aom_image_t *img_shifted = *img_shifted_ptr;

   const aom_img_fmt_t shifted_fmt = output_bit_depth == 8
                                         ? img->fmt & ~AOM_IMG_FMT_HIGHBITDEPTH
                                         : img->fmt | AOM_IMG_FMT_HIGHBITDEPTH;

   if (shifted_fmt != img->fmt || output_bit_depth != img->bit_depth) {
     if (img_shifted &&
         img_shifted_realloc_required(img, img_shifted, shifted_fmt)) {
       aom_img_free(img_shifted);
       img_shifted = NULL;
     }
     if (img_shifted) {
       img_shifted->monochrome = img->monochrome;
     }
     if (!img_shifted) {
       img_shifted = aom_img_alloc(NULL, shifted_fmt, img->d_w, img->d_h, 16);
       img_shifted->bit_depth = output_bit_depth;
       img_shifted->monochrome = img->monochrome;
       img_shifted->csp = img->csp;
     }
     if (output_bit_depth > img->bit_depth) {
       aom_img_upshift(img_shifted, img, output_bit_depth - img->bit_depth);
     } else {
       aom_img_downshift(img_shifted, img, img->bit_depth - output_bit_depth);
     }
     *img_shifted_ptr = img_shifted;
     *img_ptr = img_shifted;
   }
 }

 // Related to I420, NV12 format has one luma "luminance" plane Y and one plane
 // with U and V values interleaved.
 void aom_img_write_nv12(const aom_image_t *img, FILE *file) {
   // Y plane
   const unsigned char *buf = img->planes[0];
   int stride = img->stride[0];
   int w = aom_img_plane_width(img, 0) *
           ((img->fmt & AOM_IMG_FMT_HIGHBITDEPTH) ? 2 : 1);
   int h = aom_img_plane_height(img, 0);
   int x, y;

   for (y = 0; y < h; ++y) {
     fwrite(buf, 1, w, file);
     buf += stride;
   }

   // Interleaved U and V plane
   const unsigned char *ubuf = img->planes[1];
   const unsigned char *vbuf = img->planes[2];
   const size_t size = (img->fmt & AOM_IMG_FMT_HIGHBITDEPTH) ? 2 : 1;
   stride = img->stride[1];
   w = aom_img_plane_width(img, 1);
   h = aom_img_plane_height(img, 1);

   for (y = 0; y < h; ++y) {
     for (x = 0; x < w; ++x) {
       fwrite(ubuf, size, 1, file);
       fwrite(vbuf, size, 1, file);
       ubuf += size;
       vbuf += size;
     }
     ubuf += (stride - w * size);
     vbuf += (stride - w * size);
   }
 }
	/*
	* 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 <math.h>
	#include <stdarg.h>
	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>

	#include "common/tools_common.h"

	#if CONFIG_AV1_ENCODER
	#include "aom/aomcx.h"
	#endif

	#if CONFIG_AV1_DECODER
	#include "aom/aomdx.h"
	#endif

	#if defined(_WIN32) \|\| defined(__OS2__)
	#include <io.h>
	#include <fcntl.h>

	#ifdef __OS2__
	#define _setmode setmode
	#define _fileno fileno
	#define _O_BINARY O_BINARY
	#endif
	#endif

	#define LOG_ERROR(label) \
	do { \
	const char *l = label; \
	va_list ap; \
	va_start(ap, fmt); \
	if (l) fprintf(stderr, "%s: ", l); \
	vfprintf(stderr, fmt, ap); \
	fprintf(stderr, "\n"); \
	va_end(ap); \
	} while (0)

	FILE set_binary_mode(FILE stream) {
	(void)stream;
	#if defined(_WIN32) \|\| defined(__OS2__)
	_setmode(_fileno(stream), _O_BINARY);
	#endif
	return stream;
	}

	void die(const char *fmt, ...) {
	LOG_ERROR(NULL);
	usage_exit();
	}

	void fatal(const char *fmt, ...) {
	LOG_ERROR("Fatal");
	exit(EXIT_FAILURE);
	}

	void aom_tools_warn(const char *fmt, ...) { LOG_ERROR("Warning"); }

	void die_codec(aom_codec_ctx_t ctx, const char s) {
	const char *detail = aom_codec_error_detail(ctx);

	printf("%s: %s\n", s, aom_codec_error(ctx));
	if (detail) printf(" %s\n", detail);
	exit(EXIT_FAILURE);
	}

	int read_yuv_frame(struct AvxInputContext input_ctx, aom_image_t yuv_frame) {
	FILE *f = input_ctx->file;
	struct FileTypeDetectionBuffer *detect = &input_ctx->detect;
	int plane = 0;
	int shortread = 0;
	const int bytespp = (yuv_frame->fmt & AOM_IMG_FMT_HIGHBITDEPTH) ? 2 : 1;

	for (plane = 0; plane < 3; ++plane) {
	uint8_t *ptr;
	const int w = aom_img_plane_width(yuv_frame, plane);
	const int h = aom_img_plane_height(yuv_frame, plane);
	int r;

	/* Determine the correct plane based on the image format. The for-loop
	* always counts in Y,U,V order, but this may not match the order of
	* the data on disk.
	*/
	switch (plane) {
	case 1:
	ptr =
	yuv_frame->planes[yuv_frame->fmt == AOM_IMG_FMT_YV12 ? AOM_PLANE_V
	: AOM_PLANE_U];
	break;
	case 2:
	ptr =
	yuv_frame->planes[yuv_frame->fmt == AOM_IMG_FMT_YV12 ? AOM_PLANE_U
	: AOM_PLANE_V];
	break;
	default: ptr = yuv_frame->planes[plane];
	}

	for (r = 0; r < h; ++r) {
	size_t needed = w * bytespp;
	size_t buf_position = 0;
	const size_t left = detect->buf_read - detect->position;
	if (left > 0) {
	const size_t more = (left < needed) ? left : needed;
	memcpy(ptr, detect->buf + detect->position, more);
	buf_position = more;
	needed -= more;
	detect->position += more;
	}
	if (needed > 0) {
	shortread \|= (fread(ptr + buf_position, 1, needed, f) < needed);
	}

	ptr += yuv_frame->stride[plane];
	}
	}

	return shortread;
	}

	struct CodecInfo {
	// Pointer to a function of zero arguments that returns an aom_codec_iface_t.
	aom_codec_iface_t (const interface)();
	char *short_name;
	uint32_t fourcc;
	};

	#if CONFIG_AV1_ENCODER
	static const struct CodecInfo aom_encoders[] = {
	{ &aom_codec_av1_cx, "av1", AV1_FOURCC },
	};

	int get_aom_encoder_count(void) {
	return sizeof(aom_encoders) / sizeof(aom_encoders[0]);
	}

	aom_codec_iface_t *get_aom_encoder_by_index(int i) {
	assert(i >= 0 && i < get_aom_encoder_count());
	return aom_encoders[i].interface();
	}

	aom_codec_iface_t get_aom_encoder_by_short_name(const char name) {
	for (int i = 0; i < get_aom_encoder_count(); ++i) {
	const struct CodecInfo *info = &aom_encoders[i];
	if (strcmp(info->short_name, name) == 0) return info->interface();
	}
	return NULL;
	}

	uint32_t get_fourcc_by_aom_encoder(aom_codec_iface_t *iface) {
	for (int i = 0; i < get_aom_encoder_count(); ++i) {
	const struct CodecInfo *info = &aom_encoders[i];
	if (info->interface() == iface) {
	return info->fourcc;
	}
	}
	return 0;
	}

	const char get_short_name_by_aom_encoder(aom_codec_iface_t iface) {
	for (int i = 0; i < get_aom_encoder_count(); ++i) {
	const struct CodecInfo *info = &aom_encoders[i];
	if (info->interface() == iface) {
	return info->short_name;
	}
	}
	return NULL;
	}

	#endif // CONFIG_AV1_ENCODER

	#if CONFIG_AV1_DECODER
	static const struct CodecInfo aom_decoders[] = {
	{ &aom_codec_av1_dx, "av1", AV1_FOURCC },
	};

	int get_aom_decoder_count(void) {
	return sizeof(aom_decoders) / sizeof(aom_decoders[0]);
	}

	aom_codec_iface_t *get_aom_decoder_by_index(int i) {
	assert(i >= 0 && i < get_aom_decoder_count());
	return aom_decoders[i].interface();
	}

	aom_codec_iface_t get_aom_decoder_by_short_name(const char name) {
	for (int i = 0; i < get_aom_decoder_count(); ++i) {
	const struct CodecInfo *info = &aom_decoders[i];
	if (strcmp(info->short_name, name) == 0) return info->interface();
	}
	return NULL;
	}

	aom_codec_iface_t *get_aom_decoder_by_fourcc(uint32_t fourcc) {
	for (int i = 0; i < get_aom_decoder_count(); ++i) {
	const struct CodecInfo *info = &aom_decoders[i];
	if (info->fourcc == fourcc) return info->interface();
	}
	return NULL;
	}

	const char get_short_name_by_aom_decoder(aom_codec_iface_t iface) {
	for (int i = 0; i < get_aom_decoder_count(); ++i) {
	const struct CodecInfo *info = &aom_decoders[i];
	if (info->interface() == iface) {
	return info->short_name;
	}
	}
	return NULL;
	}

	uint32_t get_fourcc_by_aom_decoder(aom_codec_iface_t *iface) {
	for (int i = 0; i < get_aom_decoder_count(); ++i) {
	const struct CodecInfo *info = &aom_decoders[i];
	if (info->interface() == iface) {
	return info->fourcc;
	}
	}
	return 0;
	}

	#endif // CONFIG_AV1_DECODER

	void aom_img_write(const aom_image_t img, FILE file) {
	int plane;

	for (plane = 0; plane < 3; ++plane) {
	const unsigned char *buf = img->planes[plane];
	const int stride = img->stride[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);
	int y;

	for (y = 0; y < h; ++y) {
	fwrite(buf, 1, w, file);
	buf += stride;
	}
	}
	}

	int aom_img_read(aom_image_t img, FILE file) {
	int plane;

	for (plane = 0; plane < 3; ++plane) {
	unsigned char *buf = img->planes[plane];
	const int stride = img->stride[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);
	int y;

	for (y = 0; y < h; ++y) {
	if (fread(buf, 1, w, file) != (size_t)w) return 0;
	buf += stride;
	}
	}

	return 1;
	}

	// TODO(dkovalev) change sse_to_psnr signature: double -> int64_t
	double sse_to_psnr(double samples, double peak, double sse) {
	static const double kMaxPSNR = 100.0;

	if (sse > 0.0) {
	const double psnr = 10.0 * log10(samples * peak * peak / sse);
	return psnr > kMaxPSNR ? kMaxPSNR : psnr;
	} else {
	return kMaxPSNR;
	}
	}

	// TODO(debargha): Consolidate the functions below into a separate file.
	static void highbd_img_upshift(aom_image_t dst, const aom_image_t src,
	int input_shift) {
	// Note the offset is 1 less than half.
	const int offset = input_shift > 0 ? (1 << (input_shift - 1)) - 1 : 0;
	int plane;
	if (dst->d_w != src->d_w \|\| dst->d_h != src->d_h \|\|
	dst->x_chroma_shift != src->x_chroma_shift \|\|
	dst->y_chroma_shift != src->y_chroma_shift \|\| dst->fmt != src->fmt \|\|
	input_shift < 0) {
	fatal("Unsupported image conversion");
	}
	switch (src->fmt) {
	case AOM_IMG_FMT_I42016:
	case AOM_IMG_FMT_I42216:
	case AOM_IMG_FMT_I44416: break;
	default: fatal("Unsupported image conversion"); break;
	}
	for (plane = 0; plane < 3; plane++) {
	int w = src->d_w;
	int h = src->d_h;
	int x, y;
	if (plane) {
	w = (w + src->x_chroma_shift) >> src->x_chroma_shift;
	h = (h + src->y_chroma_shift) >> src->y_chroma_shift;
	}
	for (y = 0; y < h; y++) {
	const uint16_t *p_src =
	(const uint16_t )(src->planes[plane] + y src->stride[plane]);
	uint16_t *p_dst =
	(uint16_t )(dst->planes[plane] + y dst->stride[plane]);
	for (x = 0; x < w; x++) p_dst++ = (p_src++ << input_shift) + offset;
	}
	}
	}

	static void lowbd_img_upshift(aom_image_t dst, const aom_image_t src,
	int input_shift) {
	// Note the offset is 1 less than half.
	const int offset = input_shift > 0 ? (1 << (input_shift - 1)) - 1 : 0;
	int plane;
	if (dst->d_w != src->d_w \|\| dst->d_h != src->d_h \|\|
	dst->x_chroma_shift != src->x_chroma_shift \|\|
	dst->y_chroma_shift != src->y_chroma_shift \|\|
	dst->fmt != src->fmt + AOM_IMG_FMT_HIGHBITDEPTH \|\| input_shift < 0) {
	fatal("Unsupported image conversion");
	}
	switch (src->fmt) {
	case AOM_IMG_FMT_YV12:
	case AOM_IMG_FMT_I420:
	case AOM_IMG_FMT_I422:
	case AOM_IMG_FMT_I444: break;
	default: fatal("Unsupported image conversion"); break;
	}
	for (plane = 0; plane < 3; plane++) {
	int w = src->d_w;
	int h = src->d_h;
	int x, y;
	if (plane) {
	w = (w + src->x_chroma_shift) >> src->x_chroma_shift;
	h = (h + src->y_chroma_shift) >> src->y_chroma_shift;
	}
	for (y = 0; y < h; y++) {
	const uint8_t p_src = src->planes[plane] + y src->stride[plane];
	uint16_t *p_dst =
	(uint16_t )(dst->planes[plane] + y dst->stride[plane]);
	for (x = 0; x < w; x++) {
	p_dst++ = (p_src++ << input_shift) + offset;
	}
	}
	}
	}

	void aom_img_upshift(aom_image_t dst, const aom_image_t src,
	int input_shift) {
	if (src->fmt & AOM_IMG_FMT_HIGHBITDEPTH) {
	highbd_img_upshift(dst, src, input_shift);
	} else {
	lowbd_img_upshift(dst, src, input_shift);
	}
	}

	void aom_img_truncate_16_to_8(aom_image_t dst, const aom_image_t src) {
	int plane;
	if (dst->fmt + AOM_IMG_FMT_HIGHBITDEPTH != src->fmt \|\| dst->d_w != src->d_w \|\|
	dst->d_h != src->d_h \|\| dst->x_chroma_shift != src->x_chroma_shift \|\|
	dst->y_chroma_shift != src->y_chroma_shift) {
	fatal("Unsupported image conversion");
	}
	switch (dst->fmt) {
	case AOM_IMG_FMT_I420:
	case AOM_IMG_FMT_I422:
	case AOM_IMG_FMT_I444: break;
	default: fatal("Unsupported image conversion"); break;
	}
	for (plane = 0; plane < 3; plane++) {
	int w = src->d_w;
	int h = src->d_h;
	int x, y;
	if (plane) {
	w = (w + src->x_chroma_shift) >> src->x_chroma_shift;
	h = (h + src->y_chroma_shift) >> src->y_chroma_shift;
	}
	for (y = 0; y < h; y++) {
	const uint16_t *p_src =
	(const uint16_t )(src->planes[plane] + y src->stride[plane]);
	uint8_t p_dst = dst->planes[plane] + y dst->stride[plane];
	for (x = 0; x < w; x++) {
	p_dst++ = (uint8_t)(p_src++);
	}
	}
	}
	}

	static void highbd_img_downshift(aom_image_t dst, const aom_image_t src,
	int down_shift) {
	int plane;
	if (dst->d_w != src->d_w \|\| dst->d_h != src->d_h \|\|
	dst->x_chroma_shift != src->x_chroma_shift \|\|
	dst->y_chroma_shift != src->y_chroma_shift \|\| dst->fmt != src->fmt \|\|
	down_shift < 0) {
	fatal("Unsupported image conversion");
	}
	switch (src->fmt) {
	case AOM_IMG_FMT_I42016:
	case AOM_IMG_FMT_I42216:
	case AOM_IMG_FMT_I44416: break;
	default: fatal("Unsupported image conversion"); break;
	}
	for (plane = 0; plane < 3; plane++) {
	int w = src->d_w;
	int h = src->d_h;
	int x, y;
	if (plane) {
	w = (w + src->x_chroma_shift) >> src->x_chroma_shift;
	h = (h + src->y_chroma_shift) >> src->y_chroma_shift;
	}
	for (y = 0; y < h; y++) {
	const uint16_t *p_src =
	(const uint16_t )(src->planes[plane] + y src->stride[plane]);
	uint16_t *p_dst =
	(uint16_t )(dst->planes[plane] + y dst->stride[plane]);
	for (x = 0; x < w; x++) p_dst++ = p_src++ >> down_shift;
	}
	}
	}

	static void lowbd_img_downshift(aom_image_t dst, const aom_image_t src,
	int down_shift) {
	int plane;
	if (dst->d_w != src->d_w \|\| dst->d_h != src->d_h \|\|
	dst->x_chroma_shift != src->x_chroma_shift \|\|
	dst->y_chroma_shift != src->y_chroma_shift \|\|
	src->fmt != dst->fmt + AOM_IMG_FMT_HIGHBITDEPTH \|\| down_shift < 0) {
	fatal("Unsupported image conversion");
	}
	switch (dst->fmt) {
	case AOM_IMG_FMT_I420:
	case AOM_IMG_FMT_I422:
	case AOM_IMG_FMT_I444: break;
	default: fatal("Unsupported image conversion"); break;
	}
	for (plane = 0; plane < 3; plane++) {
	int w = src->d_w;
	int h = src->d_h;
	int x, y;
	if (plane) {
	w = (w + src->x_chroma_shift) >> src->x_chroma_shift;
	h = (h + src->y_chroma_shift) >> src->y_chroma_shift;
	}
	for (y = 0; y < h; y++) {
	const uint16_t *p_src =
	(const uint16_t )(src->planes[plane] + y src->stride[plane]);
	uint8_t p_dst = dst->planes[plane] + y dst->stride[plane];
	for (x = 0; x < w; x++) {
	p_dst++ = p_src++ >> down_shift;
	}
	}
	}
	}

	void aom_img_downshift(aom_image_t dst, const aom_image_t src,
	int down_shift) {
	if (dst->fmt & AOM_IMG_FMT_HIGHBITDEPTH) {
	highbd_img_downshift(dst, src, down_shift);
	} else {
	lowbd_img_downshift(dst, src, down_shift);
	}
	}

	static int img_shifted_realloc_required(const aom_image_t *img,
	const aom_image_t *shifted,
	aom_img_fmt_t required_fmt) {
	return img->d_w != shifted->d_w \|\| img->d_h != shifted->d_h \|\|
	required_fmt != shifted->fmt;
	}

	void aom_shift_img(unsigned int output_bit_depth, aom_image_t **img_ptr,
	aom_image_t **img_shifted_ptr) {
	aom_image_t img = img_ptr;
	aom_image_t img_shifted = img_shifted_ptr;

	const aom_img_fmt_t shifted_fmt = output_bit_depth == 8
	? img->fmt & ~AOM_IMG_FMT_HIGHBITDEPTH
	: img->fmt \| AOM_IMG_FMT_HIGHBITDEPTH;

	if (shifted_fmt != img->fmt \|\| output_bit_depth != img->bit_depth) {
	if (img_shifted &&
	img_shifted_realloc_required(img, img_shifted, shifted_fmt)) {
	aom_img_free(img_shifted);
	img_shifted = NULL;
	}
	if (img_shifted) {
	img_shifted->monochrome = img->monochrome;
	}
	if (!img_shifted) {
	img_shifted = aom_img_alloc(NULL, shifted_fmt, img->d_w, img->d_h, 16);
	img_shifted->bit_depth = output_bit_depth;
	img_shifted->monochrome = img->monochrome;
	img_shifted->csp = img->csp;
	}
	if (output_bit_depth > img->bit_depth) {
	aom_img_upshift(img_shifted, img, output_bit_depth - img->bit_depth);
	} else {
	aom_img_downshift(img_shifted, img, img->bit_depth - output_bit_depth);
	}
	*img_shifted_ptr = img_shifted;
	*img_ptr = img_shifted;
	}
	}

	// Related to I420, NV12 format has one luma "luminance" plane Y and one plane
	// with U and V values interleaved.
	void aom_img_write_nv12(const aom_image_t img, FILE file) {
	// Y plane
	const unsigned char *buf = img->planes[0];
	int stride = img->stride[0];
	int w = aom_img_plane_width(img, 0) *
	((img->fmt & AOM_IMG_FMT_HIGHBITDEPTH) ? 2 : 1);
	int h = aom_img_plane_height(img, 0);
	int x, y;

	for (y = 0; y < h; ++y) {
	fwrite(buf, 1, w, file);
	buf += stride;
	}

	// Interleaved U and V plane
	const unsigned char *ubuf = img->planes[1];
	const unsigned char *vbuf = img->planes[2];
	const size_t size = (img->fmt & AOM_IMG_FMT_HIGHBITDEPTH) ? 2 : 1;
	stride = img->stride[1];
	w = aom_img_plane_width(img, 1);
	h = aom_img_plane_height(img, 1);

	for (y = 0; y < h; ++y) {
	for (x = 0; x < w; ++x) {
	fwrite(ubuf, size, 1, file);
	fwrite(vbuf, size, 1, file);
	ubuf += size;
	vbuf += size;
	}
	ubuf += (stride - w * size);
	vbuf += (stride - w * size);
	}
	}