libavcodec/hapenc.c - manifest_repos/ffmpeg - Git at Google

 /*
  * Vidvox Hap encoder
  * Copyright (C) 2015 Vittorio Giovara <vittorio.giovara@gmail.com>
  * Copyright (C) 2015 Tom Butterworth <bangnoise@gmail.com>
  *
  * This file is part of FFmpeg.
  *
  * FFmpeg is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
  * FFmpeg is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
  * License along with FFmpeg; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */

 /**
  * @file
  * Hap encoder
  *
  * Fourcc: Hap1, Hap5, HapY
  *
  * https://github.com/Vidvox/hap/blob/master/documentation/HapVideoDRAFT.md
  */

 #include <stdint.h>
 #include "snappy-c.h"

 #include "libavutil/frame.h"
 #include "libavutil/imgutils.h"
 #include "libavutil/intreadwrite.h"
 #include "libavutil/opt.h"

 #include "avcodec.h"
 #include "bytestream.h"
 #include "hap.h"
 #include "internal.h"
 #include "texturedsp.h"

 #define HAP_MAX_CHUNKS 64

 enum HapHeaderLength {
     /* Short header: four bytes with a 24 bit size value */
     HAP_HDR_SHORT = 4,
     /* Long header: eight bytes with a 32 bit size value */
     HAP_HDR_LONG = 8,
 };

 static int compress_texture(AVCodecContext *avctx, uint8_t *out, int out_length, const AVFrame *f)
 {
     HapContext *ctx = avctx->priv_data;
     int i, j;

     if (ctx->tex_size > out_length)
         return AVERROR_BUFFER_TOO_SMALL;

     for (j = 0; j < avctx->height; j += 4) {
         for (i = 0; i < avctx->width; i += 4) {
             uint8_t *p = f->data[0] + i * 4 + j * f->linesize[0];
             const int step = ctx->tex_fun(out, f->linesize[0], p);
             out += step;
         }
     }

     return 0;
 }

 /* section_length does not include the header */
 static void hap_write_section_header(PutByteContext *pbc,
                                      enum HapHeaderLength header_length,
                                      int section_length,
                                      enum HapSectionType section_type)
 {
     /* The first three bytes are the length of the section (not including the
      * header) or zero if using an eight-byte header.
      * For an eight-byte header, the length is in the last four bytes.
      * The fourth byte stores the section type. */
     bytestream2_put_le24(pbc, header_length == HAP_HDR_LONG ? 0 : section_length);
     bytestream2_put_byte(pbc, section_type);

     if (header_length == HAP_HDR_LONG) {
         bytestream2_put_le32(pbc, section_length);
     }
 }

 static int hap_compress_frame(AVCodecContext *avctx, uint8_t *dst)
 {
     HapContext *ctx = avctx->priv_data;
     int i, final_size = 0;

     for (i = 0; i < ctx->chunk_count; i++) {
         HapChunk *chunk = &ctx->chunks[i];
         uint8_t *chunk_src, *chunk_dst;
         int ret;

         if (i == 0) {
             chunk->compressed_offset = 0;
         } else {
             chunk->compressed_offset = ctx->chunks[i-1].compressed_offset
                                        + ctx->chunks[i-1].compressed_size;
         }
         chunk->uncompressed_size = ctx->tex_size / ctx->chunk_count;
         chunk->uncompressed_offset = i * chunk->uncompressed_size;
         chunk->compressed_size = ctx->max_snappy;
         chunk_src = ctx->tex_buf + chunk->uncompressed_offset;
         chunk_dst = dst + chunk->compressed_offset;

         /* Compress with snappy too, write directly on packet buffer. */
         ret = snappy_compress(chunk_src, chunk->uncompressed_size,
                               chunk_dst, &chunk->compressed_size);
         if (ret != SNAPPY_OK) {
             av_log(avctx, AV_LOG_ERROR, "Snappy compress error.\n");
             return AVERROR_BUG;
         }

         /* If there is no gain from snappy, just use the raw texture. */
         if (chunk->compressed_size >= chunk->uncompressed_size) {
             av_log(avctx, AV_LOG_VERBOSE,
                    "Snappy buffer bigger than uncompressed (%"SIZE_SPECIFIER" >= %"SIZE_SPECIFIER" bytes).\n",
                    chunk->compressed_size, chunk->uncompressed_size);
             memcpy(chunk_dst, chunk_src, chunk->uncompressed_size);
             chunk->compressor = HAP_COMP_NONE;
             chunk->compressed_size = chunk->uncompressed_size;
         } else {
             chunk->compressor = HAP_COMP_SNAPPY;
         }

         final_size += chunk->compressed_size;
     }

     return final_size;
 }

 static int hap_decode_instructions_length(HapContext *ctx)
 {
     /*    Second-Stage Compressor Table (one byte per entry)
      *  + Chunk Size Table (four bytes per entry)
      *  + headers for both sections (short versions)
      *  = chunk_count + (4 * chunk_count) + 4 + 4 */
     return (5 * ctx->chunk_count) + 8;
 }

 static int hap_header_length(HapContext *ctx)
 {
     /* Top section header (long version) */
     int length = HAP_HDR_LONG;

     if (ctx->chunk_count > 1) {
         /* Decode Instructions header (short) + Decode Instructions Container */
         length += HAP_HDR_SHORT + hap_decode_instructions_length(ctx);
     }

     return length;
 }

 static void hap_write_frame_header(HapContext *ctx, uint8_t *dst, int frame_length)
 {
     PutByteContext pbc;
     int i;

     bytestream2_init_writer(&pbc, dst, frame_length);
     if (ctx->chunk_count == 1) {
         /* Write a simple header */
         hap_write_section_header(&pbc, HAP_HDR_LONG, frame_length - 8,
                                  ctx->chunks[0].compressor | ctx->opt_tex_fmt);
     } else {
         /* Write a complex header with Decode Instructions Container */
         hap_write_section_header(&pbc, HAP_HDR_LONG, frame_length - 8,
                                  HAP_COMP_COMPLEX | ctx->opt_tex_fmt);
         hap_write_section_header(&pbc, HAP_HDR_SHORT, hap_decode_instructions_length(ctx),
                                  HAP_ST_DECODE_INSTRUCTIONS);
         hap_write_section_header(&pbc, HAP_HDR_SHORT, ctx->chunk_count,
                                  HAP_ST_COMPRESSOR_TABLE);

         for (i = 0; i < ctx->chunk_count; i++) {
             bytestream2_put_byte(&pbc, ctx->chunks[i].compressor >> 4);
         }

         hap_write_section_header(&pbc, HAP_HDR_SHORT, ctx->chunk_count * 4,
                                  HAP_ST_SIZE_TABLE);

         for (i = 0; i < ctx->chunk_count; i++) {
             bytestream2_put_le32(&pbc, ctx->chunks[i].compressed_size);
         }
     }
 }

 static int hap_encode(AVCodecContext *avctx, AVPacket *pkt,
                       const AVFrame *frame, int *got_packet)
 {
     HapContext *ctx = avctx->priv_data;
     int header_length = hap_header_length(ctx);
     int final_data_size, ret;
     int pktsize = FFMAX(ctx->tex_size, ctx->max_snappy * ctx->chunk_count) + header_length;

     /* Allocate maximum size packet, shrink later. */
     ret = ff_alloc_packet2(avctx, pkt, pktsize, header_length);
     if (ret < 0)
         return ret;

     if (ctx->opt_compressor == HAP_COMP_NONE) {
         /* DXTC compression directly to the packet buffer. */
         ret = compress_texture(avctx, pkt->data + header_length, pkt->size - header_length, frame);
         if (ret < 0)
             return ret;

         ctx->chunks[0].compressor = HAP_COMP_NONE;
         final_data_size = ctx->tex_size;
     } else {
         /* DXTC compression. */
         ret = compress_texture(avctx, ctx->tex_buf, ctx->tex_size, frame);
         if (ret < 0)
             return ret;

         /* Compress (using Snappy) the frame */
         final_data_size = hap_compress_frame(avctx, pkt->data + header_length);
         if (final_data_size < 0)
             return final_data_size;
     }

     /* Write header at the start. */
     hap_write_frame_header(ctx, pkt->data, final_data_size + header_length);

     av_shrink_packet(pkt, final_data_size + header_length);
     pkt->flags |= AV_PKT_FLAG_KEY;
     *got_packet = 1;
     return 0;
 }

 static av_cold int hap_init(AVCodecContext *avctx)
 {
     HapContext *ctx = avctx->priv_data;
     int ratio;
     int corrected_chunk_count;
     int ret = av_image_check_size(avctx->width, avctx->height, 0, avctx);

     if (ret < 0) {
         av_log(avctx, AV_LOG_ERROR, "Invalid video size %dx%d.\n",
                avctx->width, avctx->height);
         return ret;
     }

     if (avctx->width % 4 || avctx->height % 4) {
         av_log(avctx, AV_LOG_ERROR, "Video size %dx%d is not multiple of 4.\n",
                avctx->width, avctx->height);
         return AVERROR_INVALIDDATA;
     }

     ff_texturedspenc_init(&ctx->dxtc);

     switch (ctx->opt_tex_fmt) {
     case HAP_FMT_RGBDXT1:
         ratio = 8;
         avctx->codec_tag = MKTAG('H', 'a', 'p', '1');
         avctx->bits_per_coded_sample = 24;
         ctx->tex_fun = ctx->dxtc.dxt1_block;
         break;
     case HAP_FMT_RGBADXT5:
         ratio = 4;
         avctx->codec_tag = MKTAG('H', 'a', 'p', '5');
         avctx->bits_per_coded_sample = 32;
         ctx->tex_fun = ctx->dxtc.dxt5_block;
         break;
     case HAP_FMT_YCOCGDXT5:
         ratio = 4;
         avctx->codec_tag = MKTAG('H', 'a', 'p', 'Y');
         avctx->bits_per_coded_sample = 24;
         ctx->tex_fun = ctx->dxtc.dxt5ys_block;
         break;
     default:
         av_log(avctx, AV_LOG_ERROR, "Invalid format %02X\n", ctx->opt_tex_fmt);
         return AVERROR_INVALIDDATA;
     }

     /* Texture compression ratio is constant, so can we computer
      * beforehand the final size of the uncompressed buffer. */
     ctx->tex_size   = FFALIGN(avctx->width,  TEXTURE_BLOCK_W) *
                       FFALIGN(avctx->height, TEXTURE_BLOCK_H) * 4 / ratio;

     switch (ctx->opt_compressor) {
     case HAP_COMP_NONE:
         /* No benefit chunking uncompressed data */
         corrected_chunk_count = 1;

         ctx->max_snappy = ctx->tex_size;
         ctx->tex_buf = NULL;
         break;
     case HAP_COMP_SNAPPY:
         /* Round the chunk count to divide evenly on DXT block edges */
         corrected_chunk_count = av_clip(ctx->opt_chunk_count, 1, HAP_MAX_CHUNKS);
         while ((ctx->tex_size / (64 / ratio)) % corrected_chunk_count != 0) {
             corrected_chunk_count--;
         }

         ctx->max_snappy = snappy_max_compressed_length(ctx->tex_size / corrected_chunk_count);
         ctx->tex_buf = av_malloc(ctx->tex_size);
         if (!ctx->tex_buf) {
             return AVERROR(ENOMEM);
         }
         break;
     default:
         av_log(avctx, AV_LOG_ERROR, "Invalid compresor %02X\n", ctx->opt_compressor);
         return AVERROR_INVALIDDATA;
     }
     if (corrected_chunk_count != ctx->opt_chunk_count) {
         av_log(avctx, AV_LOG_INFO, "%d chunks requested but %d used.\n",
                                     ctx->opt_chunk_count, corrected_chunk_count);
     }
     ret = ff_hap_set_chunk_count(ctx, corrected_chunk_count, 1);
     if (ret != 0)
         return ret;

     return 0;
 }

 static av_cold int hap_close(AVCodecContext *avctx)
 {
     HapContext *ctx = avctx->priv_data;

     ff_hap_free_context(ctx);

     return 0;
 }

 #define OFFSET(x) offsetof(HapContext, x)
 #define FLAGS     AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
 static const AVOption options[] = {
     { "format", NULL, OFFSET(opt_tex_fmt), AV_OPT_TYPE_INT, { .i64 = HAP_FMT_RGBDXT1 }, HAP_FMT_RGBDXT1, HAP_FMT_YCOCGDXT5, FLAGS, "format" },
         { "hap",       "Hap 1 (DXT1 textures)", 0, AV_OPT_TYPE_CONST, { .i64 = HAP_FMT_RGBDXT1   }, 0, 0, FLAGS, "format" },
         { "hap_alpha", "Hap Alpha (DXT5 textures)", 0, AV_OPT_TYPE_CONST, { .i64 = HAP_FMT_RGBADXT5  }, 0, 0, FLAGS, "format" },
         { "hap_q",     "Hap Q (DXT5-YCoCg textures)", 0, AV_OPT_TYPE_CONST, { .i64 = HAP_FMT_YCOCGDXT5 }, 0, 0, FLAGS, "format" },
     { "chunks", "chunk count", OFFSET(opt_chunk_count), AV_OPT_TYPE_INT, {.i64 = 1 }, 1, HAP_MAX_CHUNKS, FLAGS, },
     { "compressor", "second-stage compressor", OFFSET(opt_compressor), AV_OPT_TYPE_INT, { .i64 = HAP_COMP_SNAPPY }, HAP_COMP_NONE, HAP_COMP_SNAPPY, FLAGS, "compressor" },
         { "none",       "None", 0, AV_OPT_TYPE_CONST, { .i64 = HAP_COMP_NONE }, 0, 0, FLAGS, "compressor" },
         { "snappy",     "Snappy", 0, AV_OPT_TYPE_CONST, { .i64 = HAP_COMP_SNAPPY }, 0, 0, FLAGS, "compressor" },
     { NULL },
 };

 static const AVClass hapenc_class = {
     .class_name = "Hap encoder",
     .item_name  = av_default_item_name,
     .option     = options,
     .version    = LIBAVUTIL_VERSION_INT,
 };

 AVCodec ff_hap_encoder = {
     .name           = "hap",
     .long_name      = NULL_IF_CONFIG_SMALL("Vidvox Hap"),
     .type           = AVMEDIA_TYPE_VIDEO,
     .id             = AV_CODEC_ID_HAP,
     .priv_data_size = sizeof(HapContext),
     .priv_class     = &hapenc_class,
     .init           = hap_init,
     .encode2        = hap_encode,
     .close          = hap_close,
     .pix_fmts       = (const enum AVPixelFormat[]) {
         AV_PIX_FMT_RGBA, AV_PIX_FMT_NONE,
     },
     .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE |
                       FF_CODEC_CAP_INIT_CLEANUP,
 };
	/*
	* Vidvox Hap encoder
	* Copyright (C) 2015 Vittorio Giovara <vittorio.giovara@gmail.com>
	* Copyright (C) 2015 Tom Butterworth <bangnoise@gmail.com>
	*
	* This file is part of FFmpeg.
	*
	* FFmpeg is free software; you can redistribute it and/or
	* modify it under the terms of the GNU Lesser General Public
	* License as published by the Free Software Foundation; either
	* version 2.1 of the License, or (at your option) any later version.
	*
	* FFmpeg is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	* Lesser General Public License for more details.
	*
	* You should have received a copy of the GNU Lesser General Public
	* License along with FFmpeg; if not, write to the Free Software
	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
	*/

	/**
	* @file
	* Hap encoder
	*
	* Fourcc: Hap1, Hap5, HapY
	*
	* https://github.com/Vidvox/hap/blob/master/documentation/HapVideoDRAFT.md
	*/

	#include <stdint.h>
	#include "snappy-c.h"

	#include "libavutil/frame.h"
	#include "libavutil/imgutils.h"
	#include "libavutil/intreadwrite.h"
	#include "libavutil/opt.h"

	#include "avcodec.h"
	#include "bytestream.h"
	#include "hap.h"
	#include "internal.h"
	#include "texturedsp.h"

	#define HAP_MAX_CHUNKS 64

	enum HapHeaderLength {
	/* Short header: four bytes with a 24 bit size value */
	HAP_HDR_SHORT = 4,
	/* Long header: eight bytes with a 32 bit size value */
	HAP_HDR_LONG = 8,
	};

	static int compress_texture(AVCodecContext avctx, uint8_t out, int out_length, const AVFrame *f)
	{
	HapContext *ctx = avctx->priv_data;
	int i, j;

	if (ctx->tex_size > out_length)
	return AVERROR_BUFFER_TOO_SMALL;

	for (j = 0; j < avctx->height; j += 4) {
	for (i = 0; i < avctx->width; i += 4) {
	uint8_t p = f->data[0] + i 4 + j * f->linesize[0];
	const int step = ctx->tex_fun(out, f->linesize[0], p);
	out += step;
	}
	}

	return 0;
	}

	/* section_length does not include the header */
	static void hap_write_section_header(PutByteContext *pbc,
	enum HapHeaderLength header_length,
	int section_length,
	enum HapSectionType section_type)
	{
	/* The first three bytes are the length of the section (not including the
	* header) or zero if using an eight-byte header.
	* For an eight-byte header, the length is in the last four bytes.
	* The fourth byte stores the section type. */
	bytestream2_put_le24(pbc, header_length == HAP_HDR_LONG ? 0 : section_length);
	bytestream2_put_byte(pbc, section_type);

	if (header_length == HAP_HDR_LONG) {
	bytestream2_put_le32(pbc, section_length);
	}
	}

	static int hap_compress_frame(AVCodecContext avctx, uint8_t dst)
	{
	HapContext *ctx = avctx->priv_data;
	int i, final_size = 0;

	for (i = 0; i < ctx->chunk_count; i++) {
	HapChunk *chunk = &ctx->chunks[i];
	uint8_t chunk_src, chunk_dst;
	int ret;

	if (i == 0) {
	chunk->compressed_offset = 0;
	} else {
	chunk->compressed_offset = ctx->chunks[i-1].compressed_offset
	+ ctx->chunks[i-1].compressed_size;
	}
	chunk->uncompressed_size = ctx->tex_size / ctx->chunk_count;
	chunk->uncompressed_offset = i * chunk->uncompressed_size;
	chunk->compressed_size = ctx->max_snappy;
	chunk_src = ctx->tex_buf + chunk->uncompressed_offset;
	chunk_dst = dst + chunk->compressed_offset;

	/* Compress with snappy too, write directly on packet buffer. */
	ret = snappy_compress(chunk_src, chunk->uncompressed_size,
	chunk_dst, &chunk->compressed_size);
	if (ret != SNAPPY_OK) {
	av_log(avctx, AV_LOG_ERROR, "Snappy compress error.\n");
	return AVERROR_BUG;
	}

	/* If there is no gain from snappy, just use the raw texture. */
	if (chunk->compressed_size >= chunk->uncompressed_size) {
	av_log(avctx, AV_LOG_VERBOSE,
	"Snappy buffer bigger than uncompressed (%"SIZE_SPECIFIER" >= %"SIZE_SPECIFIER" bytes).\n",
	chunk->compressed_size, chunk->uncompressed_size);
	memcpy(chunk_dst, chunk_src, chunk->uncompressed_size);
	chunk->compressor = HAP_COMP_NONE;
	chunk->compressed_size = chunk->uncompressed_size;
	} else {
	chunk->compressor = HAP_COMP_SNAPPY;
	}

	final_size += chunk->compressed_size;
	}

	return final_size;
	}

	static int hap_decode_instructions_length(HapContext *ctx)
	{
	/* Second-Stage Compressor Table (one byte per entry)
	* + Chunk Size Table (four bytes per entry)
	* + headers for both sections (short versions)
	* = chunk_count + (4 * chunk_count) + 4 + 4 */
	return (5 * ctx->chunk_count) + 8;
	}

	static int hap_header_length(HapContext *ctx)
	{
	/* Top section header (long version) */
	int length = HAP_HDR_LONG;

	if (ctx->chunk_count > 1) {
	/* Decode Instructions header (short) + Decode Instructions Container */
	length += HAP_HDR_SHORT + hap_decode_instructions_length(ctx);
	}

	return length;
	}

	static void hap_write_frame_header(HapContext ctx, uint8_t dst, int frame_length)
	{
	PutByteContext pbc;
	int i;

	bytestream2_init_writer(&pbc, dst, frame_length);
	if (ctx->chunk_count == 1) {
	/* Write a simple header */
	hap_write_section_header(&pbc, HAP_HDR_LONG, frame_length - 8,
	ctx->chunks[0].compressor \| ctx->opt_tex_fmt);
	} else {
	/* Write a complex header with Decode Instructions Container */
	hap_write_section_header(&pbc, HAP_HDR_LONG, frame_length - 8,
	HAP_COMP_COMPLEX \| ctx->opt_tex_fmt);
	hap_write_section_header(&pbc, HAP_HDR_SHORT, hap_decode_instructions_length(ctx),
	HAP_ST_DECODE_INSTRUCTIONS);
	hap_write_section_header(&pbc, HAP_HDR_SHORT, ctx->chunk_count,
	HAP_ST_COMPRESSOR_TABLE);

	for (i = 0; i < ctx->chunk_count; i++) {
	bytestream2_put_byte(&pbc, ctx->chunks[i].compressor >> 4);
	}

	hap_write_section_header(&pbc, HAP_HDR_SHORT, ctx->chunk_count * 4,
	HAP_ST_SIZE_TABLE);

	for (i = 0; i < ctx->chunk_count; i++) {
	bytestream2_put_le32(&pbc, ctx->chunks[i].compressed_size);
	}
	}
	}

	static int hap_encode(AVCodecContext avctx, AVPacket pkt,
	const AVFrame frame, int got_packet)
	{
	HapContext *ctx = avctx->priv_data;
	int header_length = hap_header_length(ctx);
	int final_data_size, ret;
	int pktsize = FFMAX(ctx->tex_size, ctx->max_snappy * ctx->chunk_count) + header_length;

	/* Allocate maximum size packet, shrink later. */
	ret = ff_alloc_packet2(avctx, pkt, pktsize, header_length);
	if (ret < 0)
	return ret;

	if (ctx->opt_compressor == HAP_COMP_NONE) {
	/* DXTC compression directly to the packet buffer. */
	ret = compress_texture(avctx, pkt->data + header_length, pkt->size - header_length, frame);
	if (ret < 0)
	return ret;

	ctx->chunks[0].compressor = HAP_COMP_NONE;
	final_data_size = ctx->tex_size;
	} else {
	/* DXTC compression. */
	ret = compress_texture(avctx, ctx->tex_buf, ctx->tex_size, frame);
	if (ret < 0)
	return ret;

	/* Compress (using Snappy) the frame */
	final_data_size = hap_compress_frame(avctx, pkt->data + header_length);
	if (final_data_size < 0)
	return final_data_size;
	}

	/* Write header at the start. */
	hap_write_frame_header(ctx, pkt->data, final_data_size + header_length);

	av_shrink_packet(pkt, final_data_size + header_length);
	pkt->flags \|= AV_PKT_FLAG_KEY;
	*got_packet = 1;
	return 0;
	}

	static av_cold int hap_init(AVCodecContext *avctx)
	{
	HapContext *ctx = avctx->priv_data;
	int ratio;
	int corrected_chunk_count;
	int ret = av_image_check_size(avctx->width, avctx->height, 0, avctx);

	if (ret < 0) {
	av_log(avctx, AV_LOG_ERROR, "Invalid video size %dx%d.\n",
	avctx->width, avctx->height);
	return ret;
	}

	if (avctx->width % 4 \|\| avctx->height % 4) {
	av_log(avctx, AV_LOG_ERROR, "Video size %dx%d is not multiple of 4.\n",
	avctx->width, avctx->height);
	return AVERROR_INVALIDDATA;
	}

	ff_texturedspenc_init(&ctx->dxtc);

	switch (ctx->opt_tex_fmt) {
	case HAP_FMT_RGBDXT1:
	ratio = 8;
	avctx->codec_tag = MKTAG('H', 'a', 'p', '1');
	avctx->bits_per_coded_sample = 24;
	ctx->tex_fun = ctx->dxtc.dxt1_block;
	break;
	case HAP_FMT_RGBADXT5:
	ratio = 4;
	avctx->codec_tag = MKTAG('H', 'a', 'p', '5');
	avctx->bits_per_coded_sample = 32;
	ctx->tex_fun = ctx->dxtc.dxt5_block;
	break;
	case HAP_FMT_YCOCGDXT5:
	ratio = 4;
	avctx->codec_tag = MKTAG('H', 'a', 'p', 'Y');
	avctx->bits_per_coded_sample = 24;
	ctx->tex_fun = ctx->dxtc.dxt5ys_block;
	break;
	default:
	av_log(avctx, AV_LOG_ERROR, "Invalid format %02X\n", ctx->opt_tex_fmt);
	return AVERROR_INVALIDDATA;
	}

	/* Texture compression ratio is constant, so can we computer
	* beforehand the final size of the uncompressed buffer. */
	ctx->tex_size = FFALIGN(avctx->width, TEXTURE_BLOCK_W) *
	FFALIGN(avctx->height, TEXTURE_BLOCK_H) * 4 / ratio;

	switch (ctx->opt_compressor) {
	case HAP_COMP_NONE:
	/* No benefit chunking uncompressed data */
	corrected_chunk_count = 1;

	ctx->max_snappy = ctx->tex_size;
	ctx->tex_buf = NULL;
	break;
	case HAP_COMP_SNAPPY:
	/* Round the chunk count to divide evenly on DXT block edges */
	corrected_chunk_count = av_clip(ctx->opt_chunk_count, 1, HAP_MAX_CHUNKS);
	while ((ctx->tex_size / (64 / ratio)) % corrected_chunk_count != 0) {
	corrected_chunk_count--;
	}

	ctx->max_snappy = snappy_max_compressed_length(ctx->tex_size / corrected_chunk_count);
	ctx->tex_buf = av_malloc(ctx->tex_size);
	if (!ctx->tex_buf) {
	return AVERROR(ENOMEM);
	}
	break;
	default:
	av_log(avctx, AV_LOG_ERROR, "Invalid compresor %02X\n", ctx->opt_compressor);
	return AVERROR_INVALIDDATA;
	}
	if (corrected_chunk_count != ctx->opt_chunk_count) {
	av_log(avctx, AV_LOG_INFO, "%d chunks requested but %d used.\n",
	ctx->opt_chunk_count, corrected_chunk_count);
	}
	ret = ff_hap_set_chunk_count(ctx, corrected_chunk_count, 1);
	if (ret != 0)
	return ret;

	return 0;
	}

	static av_cold int hap_close(AVCodecContext *avctx)
	{
	HapContext *ctx = avctx->priv_data;

	ff_hap_free_context(ctx);

	return 0;
	}

	#define OFFSET(x) offsetof(HapContext, x)
	#define FLAGS AV_OPT_FLAG_VIDEO_PARAM \| AV_OPT_FLAG_ENCODING_PARAM
	static const AVOption options[] = {
	{ "format", NULL, OFFSET(opt_tex_fmt), AV_OPT_TYPE_INT, { .i64 = HAP_FMT_RGBDXT1 }, HAP_FMT_RGBDXT1, HAP_FMT_YCOCGDXT5, FLAGS, "format" },
	{ "hap", "Hap 1 (DXT1 textures)", 0, AV_OPT_TYPE_CONST, { .i64 = HAP_FMT_RGBDXT1 }, 0, 0, FLAGS, "format" },
	{ "hap_alpha", "Hap Alpha (DXT5 textures)", 0, AV_OPT_TYPE_CONST, { .i64 = HAP_FMT_RGBADXT5 }, 0, 0, FLAGS, "format" },
	{ "hap_q", "Hap Q (DXT5-YCoCg textures)", 0, AV_OPT_TYPE_CONST, { .i64 = HAP_FMT_YCOCGDXT5 }, 0, 0, FLAGS, "format" },
	{ "chunks", "chunk count", OFFSET(opt_chunk_count), AV_OPT_TYPE_INT, {.i64 = 1 }, 1, HAP_MAX_CHUNKS, FLAGS, },
	{ "compressor", "second-stage compressor", OFFSET(opt_compressor), AV_OPT_TYPE_INT, { .i64 = HAP_COMP_SNAPPY }, HAP_COMP_NONE, HAP_COMP_SNAPPY, FLAGS, "compressor" },
	{ "none", "None", 0, AV_OPT_TYPE_CONST, { .i64 = HAP_COMP_NONE }, 0, 0, FLAGS, "compressor" },
	{ "snappy", "Snappy", 0, AV_OPT_TYPE_CONST, { .i64 = HAP_COMP_SNAPPY }, 0, 0, FLAGS, "compressor" },
	{ NULL },
	};

	static const AVClass hapenc_class = {
	.class_name = "Hap encoder",
	.item_name = av_default_item_name,
	.option = options,
	.version = LIBAVUTIL_VERSION_INT,
	};

	AVCodec ff_hap_encoder = {
	.name = "hap",
	.long_name = NULL_IF_CONFIG_SMALL("Vidvox Hap"),
	.type = AVMEDIA_TYPE_VIDEO,
	.id = AV_CODEC_ID_HAP,
	.priv_data_size = sizeof(HapContext),
	.priv_class = &hapenc_class,
	.init = hap_init,
	.encode2 = hap_encode,
	.close = hap_close,
	.pix_fmts = (const enum AVPixelFormat[]) {
	AV_PIX_FMT_RGBA, AV_PIX_FMT_NONE,
	},
	.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE \|
	FF_CODEC_CAP_INIT_CLEANUP,
	};