Contributors: 1
Author Tokens Token Proportion Commits Commit Proportion
Philipp Zabel 1928 100.00% 4 100.00%
Total 1928 4 


/*
 * Coda multi-standard codec IP - JPEG support functions
 *
 * Copyright (C) 2014 Philipp Zabel, Pengutronix
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */

#include <linux/kernel.h>
#include <linux/swab.h>

#include "coda.h"
#include "trace.h"

#define SOI_MARKER	0xffd8
#define EOI_MARKER	0xffd9

/*
 * Typical Huffman tables for 8-bit precision luminance and
 * chrominance from JPEG ITU-T.81 (ISO/IEC 10918-1) Annex K.3
 */

static const unsigned char luma_dc_bits[16] = {
	0x00, 0x01, 0x05, 0x01, 0x01, 0x01, 0x01, 0x01,
	0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
};

static const unsigned char luma_dc_value[12] = {
	0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
	0x08, 0x09, 0x0a, 0x0b,
};

static const unsigned char chroma_dc_bits[16] = {
	0x00, 0x03, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
	0x01, 0x01, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00,
};

static const unsigned char chroma_dc_value[12] = {
	0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
	0x08, 0x09, 0x0a, 0x0b,
};

static const unsigned char luma_ac_bits[16] = {
	0x00, 0x02, 0x01, 0x03, 0x03, 0x02, 0x04, 0x03,
	0x05, 0x05, 0x04, 0x04, 0x00, 0x00, 0x01, 0x7d,
};

static const unsigned char luma_ac_value[162 + 2] = {
	0x01, 0x02, 0x03, 0x00, 0x04, 0x11, 0x05, 0x12,
	0x21, 0x31, 0x41, 0x06, 0x13, 0x51, 0x61, 0x07,
	0x22, 0x71, 0x14, 0x32, 0x81, 0x91, 0xa1, 0x08,
	0x23, 0x42, 0xb1, 0xc1, 0x15, 0x52, 0xd1, 0xf0,
	0x24, 0x33, 0x62, 0x72, 0x82, 0x09, 0x0a, 0x16,
	0x17, 0x18, 0x19, 0x1a, 0x25, 0x26, 0x27, 0x28,
	0x29, 0x2a, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39,
	0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49,
	0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59,
	0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69,
	0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79,
	0x7a, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89,
	0x8a, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98,
	0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,
	0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6,
	0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3, 0xc4, 0xc5,
	0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 0xd3, 0xd4,
	0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xe1, 0xe2,
	0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea,
	0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8,
	0xf9, 0xfa, /* padded to 32-bit */
};

static const unsigned char chroma_ac_bits[16] = {
	0x00, 0x02, 0x01, 0x02, 0x04, 0x04, 0x03, 0x04,
	0x07, 0x05, 0x04, 0x04, 0x00, 0x01, 0x02, 0x77,
};

static const unsigned char chroma_ac_value[162 + 2] = {
	0x00, 0x01, 0x02, 0x03, 0x11, 0x04, 0x05, 0x21,
	0x31, 0x06, 0x12, 0x41, 0x51, 0x07, 0x61, 0x71,
	0x13, 0x22, 0x32, 0x81, 0x08, 0x14, 0x42, 0x91,
	0xa1, 0xb1, 0xc1, 0x09, 0x23, 0x33, 0x52, 0xf0,
	0x15, 0x62, 0x72, 0xd1, 0x0a, 0x16, 0x24, 0x34,
	0xe1, 0x25, 0xf1, 0x17, 0x18, 0x19, 0x1a, 0x26,
	0x27, 0x28, 0x29, 0x2a, 0x35, 0x36, 0x37, 0x38,
	0x39, 0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48,
	0x49, 0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58,
	0x59, 0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68,
	0x69, 0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78,
	0x79, 0x7a, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
	0x88, 0x89, 0x8a, 0x92, 0x93, 0x94, 0x95, 0x96,
	0x97, 0x98, 0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5,
	0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4,
	0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3,
	0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2,
	0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda,
	0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9,
	0xea, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8,
	0xf9, 0xfa, /* padded to 32-bit */
};

/*
 * Quantization tables for luminance and chrominance components in
 * zig-zag scan order from the Freescale i.MX VPU libaries
 */

static unsigned char luma_q[64] = {
	0x06, 0x04, 0x04, 0x04, 0x05, 0x04, 0x06, 0x05,
	0x05, 0x06, 0x09, 0x06, 0x05, 0x06, 0x09, 0x0b,
	0x08, 0x06, 0x06, 0x08, 0x0b, 0x0c, 0x0a, 0x0a,
	0x0b, 0x0a, 0x0a, 0x0c, 0x10, 0x0c, 0x0c, 0x0c,
	0x0c, 0x0c, 0x0c, 0x10, 0x0c, 0x0c, 0x0c, 0x0c,
	0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c,
	0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c,
	0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c,
};

static unsigned char chroma_q[64] = {
	0x07, 0x07, 0x07, 0x0d, 0x0c, 0x0d, 0x18, 0x10,
	0x10, 0x18, 0x14, 0x0e, 0x0e, 0x0e, 0x14, 0x14,
	0x0e, 0x0e, 0x0e, 0x0e, 0x14, 0x11, 0x0c, 0x0c,
	0x0c, 0x0c, 0x0c, 0x11, 0x11, 0x0c, 0x0c, 0x0c,
	0x0c, 0x0c, 0x0c, 0x11, 0x0c, 0x0c, 0x0c, 0x0c,
	0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c,
	0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c,
	0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c, 0x0c,
};

struct coda_memcpy_desc {
	int offset;
	const void *src;
	size_t len;
};

static void coda_memcpy_parabuf(void *parabuf,
				const struct coda_memcpy_desc *desc)
{
	u32 *dst = parabuf + desc->offset;
	const u32 *src = desc->src;
	int len = desc->len / 4;
	int i;

	for (i = 0; i < len; i += 2) {
		dst[i + 1] = swab32(src[i]);
		dst[i] = swab32(src[i + 1]);
	}
}

int coda_jpeg_write_tables(struct coda_ctx *ctx)
{
	int i;
	static const struct coda_memcpy_desc huff[8] = {
		{ 0,   luma_dc_bits,    sizeof(luma_dc_bits)    },
		{ 16,  luma_dc_value,   sizeof(luma_dc_value)   },
		{ 32,  luma_ac_bits,    sizeof(luma_ac_bits)    },
		{ 48,  luma_ac_value,   sizeof(luma_ac_value)   },
		{ 216, chroma_dc_bits,  sizeof(chroma_dc_bits)  },
		{ 232, chroma_dc_value, sizeof(chroma_dc_value) },
		{ 248, chroma_ac_bits,  sizeof(chroma_ac_bits)  },
		{ 264, chroma_ac_value, sizeof(chroma_ac_value) },
	};
	struct coda_memcpy_desc qmat[3] = {
		{ 512, ctx->params.jpeg_qmat_tab[0], 64 },
		{ 576, ctx->params.jpeg_qmat_tab[1], 64 },
		{ 640, ctx->params.jpeg_qmat_tab[1], 64 },
	};

	/* Write huffman tables to parameter memory */
	for (i = 0; i < ARRAY_SIZE(huff); i++)
		coda_memcpy_parabuf(ctx->parabuf.vaddr, huff + i);

	/* Write Q-matrix to parameter memory */
	for (i = 0; i < ARRAY_SIZE(qmat); i++)
		coda_memcpy_parabuf(ctx->parabuf.vaddr, qmat + i);

	return 0;
}

bool coda_jpeg_check_buffer(struct coda_ctx *ctx, struct vb2_buffer *vb)
{
	void *vaddr = vb2_plane_vaddr(vb, 0);
	u16 soi, eoi;
	int len, i;

	soi = be16_to_cpup((__be16 *)vaddr);
	if (soi != SOI_MARKER)
		return false;

	len = vb2_get_plane_payload(vb, 0);
	vaddr += len - 2;
	for (i = 0; i < 32; i++) {
		eoi = be16_to_cpup((__be16 *)(vaddr - i));
		if (eoi == EOI_MARKER) {
			if (i > 0)
				vb2_set_plane_payload(vb, 0, len - i);
			return true;
		}
	}

	return false;
}

/*
 * Scale quantization table using nonlinear scaling factor
 * u8 qtab[64], scale [50,190]
 */
static void coda_scale_quant_table(u8 *q_tab, int scale)
{
	unsigned int temp;
	int i;

	for (i = 0; i < 64; i++) {
		temp = DIV_ROUND_CLOSEST((unsigned int)q_tab[i] * scale, 100);
		if (temp <= 0)
			temp = 1;
		if (temp > 255)
			temp = 255;
		q_tab[i] = (unsigned char)temp;
	}
}

void coda_set_jpeg_compression_quality(struct coda_ctx *ctx, int quality)
{
	unsigned int scale;

	ctx->params.jpeg_quality = quality;

	/* Clip quality setting to [5,100] interval */
	if (quality > 100)
		quality = 100;
	if (quality < 5)
		quality = 5;

	/*
	 * Non-linear scaling factor:
	 * [5,50] -> [1000..100], [51,100] -> [98..0]
	 */
	if (quality < 50)
		scale = 5000 / quality;
	else
		scale = 200 - 2 * quality;

	if (ctx->params.jpeg_qmat_tab[0]) {
		memcpy(ctx->params.jpeg_qmat_tab[0], luma_q, 64);
		coda_scale_quant_table(ctx->params.jpeg_qmat_tab[0], scale);
	}
	if (ctx->params.jpeg_qmat_tab[1]) {
		memcpy(ctx->params.jpeg_qmat_tab[1], chroma_q, 64);
		coda_scale_quant_table(ctx->params.jpeg_qmat_tab[1], scale);
	}
}