FFmpeg4/libavcodec/cinepakenc.c

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2023-07-02 12:20:28 +00:00
/*
* Cinepak encoder (c) 2011 Tomas Härdin
* http://titan.codemill.se/~tomhar/cinepakenc.patch
*
* Fixes and improvements, vintage decoders compatibility
* (c) 2013, 2014 Rl, Aetey Global Technologies AB
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*/
/*
* TODO:
* - optimize: color space conversion (move conversion to libswscale), ...
* MAYBE:
* - "optimally" split the frame into several non-regular areas
* using a separate codebook pair for each area and approximating
* the area by several rectangular strips (generally not full width ones)
* (use quadtree splitting? a simple fixed-granularity grid?)
*/
#include <string.h>
#include "libavutil/avassert.h"
#include "libavutil/common.h"
#include "libavutil/internal.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/lfg.h"
#include "libavutil/opt.h"
#include "avcodec.h"
#include "elbg.h"
#include "internal.h"
#define CVID_HEADER_SIZE 10
#define STRIP_HEADER_SIZE 12
#define CHUNK_HEADER_SIZE 4
#define MB_SIZE 4 //4x4 MBs
#define MB_AREA (MB_SIZE * MB_SIZE)
#define VECTOR_MAX 6 // six or four entries per vector depending on format
#define CODEBOOK_MAX 256 // size of a codebook
#define MAX_STRIPS 32 // Note: having fewer choices regarding the number of strips speeds up encoding (obviously)
#define MIN_STRIPS 1 // Note: having more strips speeds up encoding the frame (this is less obvious)
// MAX_STRIPS limits the maximum quality you can reach
// when you want high quality on high resolutions,
// MIN_STRIPS limits the minimum efficiently encodable bit rate
// on low resolutions
// the numbers are only used for brute force optimization for the first frame,
// for the following frames they are adaptively readjusted
// NOTE the decoder in ffmpeg has its own arbitrary limitation on the number
// of strips, currently 32
typedef enum CinepakMode {
MODE_V1_ONLY = 0,
MODE_V1_V4,
MODE_MC,
MODE_COUNT,
} CinepakMode;
typedef enum mb_encoding {
ENC_V1,
ENC_V4,
ENC_SKIP,
ENC_UNCERTAIN
} mb_encoding;
typedef struct mb_info {
int v1_vector; // index into v1 codebook
int v1_error; // error when using V1 encoding
int v4_vector[4]; // indices into v4 codebook
int v4_error; // error when using V4 encoding
int skip_error; // error when block is skipped (aka copied from last frame)
mb_encoding best_encoding; // last result from calculate_mode_score()
} mb_info;
typedef struct strip_info {
int v1_codebook[CODEBOOK_MAX * VECTOR_MAX];
int v4_codebook[CODEBOOK_MAX * VECTOR_MAX];
int v1_size;
int v4_size;
CinepakMode mode;
} strip_info;
typedef struct CinepakEncContext {
const AVClass *class;
AVCodecContext *avctx;
unsigned char *pict_bufs[4], *strip_buf, *frame_buf;
AVFrame *last_frame;
AVFrame *best_frame;
AVFrame *scratch_frame;
AVFrame *input_frame;
enum AVPixelFormat pix_fmt;
int w, h;
int frame_buf_size;
int curframe, keyint;
AVLFG randctx;
uint64_t lambda;
int *codebook_input;
int *codebook_closest;
mb_info *mb; // MB RD state
int min_strips; // the current limit
int max_strips; // the current limit
// options
int max_extra_cb_iterations;
int skip_empty_cb;
int min_min_strips;
int max_max_strips;
int strip_number_delta_range;
} CinepakEncContext;
#define OFFSET(x) offsetof(CinepakEncContext, x)
#define VE AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
static const AVOption options[] = {
{ "max_extra_cb_iterations", "Max extra codebook recalculation passes, more is better and slower",
OFFSET(max_extra_cb_iterations), AV_OPT_TYPE_INT, { .i64 = 2 }, 0, INT_MAX, VE },
{ "skip_empty_cb", "Avoid wasting bytes, ignore vintage MacOS decoder",
OFFSET(skip_empty_cb), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, VE },
{ "max_strips", "Limit strips/frame, vintage compatible is 1..3, otherwise the more the better",
OFFSET(max_max_strips), AV_OPT_TYPE_INT, { .i64 = 3 }, MIN_STRIPS, MAX_STRIPS, VE },
{ "min_strips", "Enforce min strips/frame, more is worse and faster, must be <= max_strips",
OFFSET(min_min_strips), AV_OPT_TYPE_INT, { .i64 = MIN_STRIPS }, MIN_STRIPS, MAX_STRIPS, VE },
{ "strip_number_adaptivity", "How fast the strip number adapts, more is slightly better, much slower",
OFFSET(strip_number_delta_range), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, MAX_STRIPS - MIN_STRIPS, VE },
{ NULL },
};
static const AVClass cinepak_class = {
.class_name = "cinepak",
.item_name = av_default_item_name,
.option = options,
.version = LIBAVUTIL_VERSION_INT,
};
static av_cold int cinepak_encode_init(AVCodecContext *avctx)
{
CinepakEncContext *s = avctx->priv_data;
int x, mb_count, strip_buf_size, frame_buf_size;
if (avctx->width & 3 || avctx->height & 3) {
av_log(avctx, AV_LOG_ERROR, "width and height must be multiples of four (got %ix%i)\n",
avctx->width, avctx->height);
return AVERROR(EINVAL);
}
if (s->min_min_strips > s->max_max_strips) {
av_log(avctx, AV_LOG_ERROR, "minimum number of strips must not exceed maximum (got %i and %i)\n",
s->min_min_strips, s->max_max_strips);
return AVERROR(EINVAL);
}
if (!(s->last_frame = av_frame_alloc()))
return AVERROR(ENOMEM);
if (!(s->best_frame = av_frame_alloc()))
goto enomem;
if (!(s->scratch_frame = av_frame_alloc()))
goto enomem;
if (avctx->pix_fmt == AV_PIX_FMT_RGB24)
if (!(s->input_frame = av_frame_alloc()))
goto enomem;
if (!(s->codebook_input = av_malloc_array((avctx->pix_fmt == AV_PIX_FMT_RGB24 ? 6 : 4) * (avctx->width * avctx->height) >> 2, sizeof(*s->codebook_input))))
goto enomem;
if (!(s->codebook_closest = av_malloc_array((avctx->width * avctx->height) >> 2, sizeof(*s->codebook_closest))))
goto enomem;
for (x = 0; x < (avctx->pix_fmt == AV_PIX_FMT_RGB24 ? 4 : 3); x++)
if (!(s->pict_bufs[x] = av_malloc((avctx->pix_fmt == AV_PIX_FMT_RGB24 ? 6 : 4) * (avctx->width * avctx->height) >> 2)))
goto enomem;
mb_count = avctx->width * avctx->height / MB_AREA;
// the largest possible chunk is 0x31 with all MBs encoded in V4 mode
// and full codebooks being replaced in INTER mode,
// which is 34 bits per MB
// and 2*256 extra flag bits per strip
strip_buf_size = STRIP_HEADER_SIZE + 3 * CHUNK_HEADER_SIZE + 2 * VECTOR_MAX * CODEBOOK_MAX + 4 * (mb_count + (mb_count + 15) / 16) + (2 * CODEBOOK_MAX) / 8;
frame_buf_size = CVID_HEADER_SIZE + s->max_max_strips * strip_buf_size;
if (!(s->strip_buf = av_malloc(strip_buf_size)))
goto enomem;
if (!(s->frame_buf = av_malloc(frame_buf_size)))
goto enomem;
if (!(s->mb = av_malloc_array(mb_count, sizeof(mb_info))))
goto enomem;
av_lfg_init(&s->randctx, 1);
s->avctx = avctx;
s->w = avctx->width;
s->h = avctx->height;
s->frame_buf_size = frame_buf_size;
s->curframe = 0;
s->keyint = avctx->keyint_min;
s->pix_fmt = avctx->pix_fmt;
// set up AVFrames
s->last_frame->data[0] = s->pict_bufs[0];
s->last_frame->linesize[0] = s->w;
s->best_frame->data[0] = s->pict_bufs[1];
s->best_frame->linesize[0] = s->w;
s->scratch_frame->data[0] = s->pict_bufs[2];
s->scratch_frame->linesize[0] = s->w;
if (s->pix_fmt == AV_PIX_FMT_RGB24) {
s->last_frame->data[1] = s->last_frame->data[0] + s->w * s->h;
s->last_frame->data[2] = s->last_frame->data[1] + ((s->w * s->h) >> 2);
s->last_frame->linesize[1] =
s->last_frame->linesize[2] = s->w >> 1;
s->best_frame->data[1] = s->best_frame->data[0] + s->w * s->h;
s->best_frame->data[2] = s->best_frame->data[1] + ((s->w * s->h) >> 2);
s->best_frame->linesize[1] =
s->best_frame->linesize[2] = s->w >> 1;
s->scratch_frame->data[1] = s->scratch_frame->data[0] + s->w * s->h;
s->scratch_frame->data[2] = s->scratch_frame->data[1] + ((s->w * s->h) >> 2);
s->scratch_frame->linesize[1] =
s->scratch_frame->linesize[2] = s->w >> 1;
s->input_frame->data[0] = s->pict_bufs[3];
s->input_frame->linesize[0] = s->w;
s->input_frame->data[1] = s->input_frame->data[0] + s->w * s->h;
s->input_frame->data[2] = s->input_frame->data[1] + ((s->w * s->h) >> 2);
s->input_frame->linesize[1] =
s->input_frame->linesize[2] = s->w >> 1;
}
s->min_strips = s->min_min_strips;
s->max_strips = s->max_max_strips;
return 0;
enomem:
av_frame_free(&s->last_frame);
av_frame_free(&s->best_frame);
av_frame_free(&s->scratch_frame);
if (avctx->pix_fmt == AV_PIX_FMT_RGB24)
av_frame_free(&s->input_frame);
av_freep(&s->codebook_input);
av_freep(&s->codebook_closest);
av_freep(&s->strip_buf);
av_freep(&s->frame_buf);
av_freep(&s->mb);
for (x = 0; x < (avctx->pix_fmt == AV_PIX_FMT_RGB24 ? 4 : 3); x++)
av_freep(&s->pict_bufs[x]);
return AVERROR(ENOMEM);
}
static int64_t calculate_mode_score(CinepakEncContext *s, int h,
strip_info *info, int report,
int *training_set_v1_shrunk,
int *training_set_v4_shrunk)
{
// score = FF_LAMBDA_SCALE * error + lambda * bits
int x;
int entry_size = s->pix_fmt == AV_PIX_FMT_RGB24 ? 6 : 4;
int mb_count = s->w * h / MB_AREA;
mb_info *mb;
int64_t score1, score2, score3;
int64_t ret = s->lambda * ((info->v1_size ? CHUNK_HEADER_SIZE + info->v1_size * entry_size : 0) +
(info->v4_size ? CHUNK_HEADER_SIZE + info->v4_size * entry_size : 0) +
CHUNK_HEADER_SIZE) << 3;
switch (info->mode) {
case MODE_V1_ONLY:
// one byte per MB
ret += s->lambda * 8 * mb_count;
// while calculating we assume all blocks are ENC_V1
for (x = 0; x < mb_count; x++) {
mb = &s->mb[x];
ret += FF_LAMBDA_SCALE * mb->v1_error;
// this function is never called for report in MODE_V1_ONLY
// if (!report)
mb->best_encoding = ENC_V1;
}
break;
case MODE_V1_V4:
// 9 or 33 bits per MB
if (report) {
// no moves between the corresponding training sets are allowed
*training_set_v1_shrunk = *training_set_v4_shrunk = 0;
for (x = 0; x < mb_count; x++) {
int mberr;
mb = &s->mb[x];
if (mb->best_encoding == ENC_V1)
score1 = s->lambda * 9 + FF_LAMBDA_SCALE * (mberr = mb->v1_error);
else
score1 = s->lambda * 33 + FF_LAMBDA_SCALE * (mberr = mb->v4_error);
ret += score1;
}
} else { // find best mode per block
for (x = 0; x < mb_count; x++) {
mb = &s->mb[x];
score1 = s->lambda * 9 + FF_LAMBDA_SCALE * mb->v1_error;
score2 = s->lambda * 33 + FF_LAMBDA_SCALE * mb->v4_error;
if (score1 <= score2) {
ret += score1;
mb->best_encoding = ENC_V1;
} else {
ret += score2;
mb->best_encoding = ENC_V4;
}
}
}
break;
case MODE_MC:
// 1, 10 or 34 bits per MB
if (report) {
int v1_shrunk = 0, v4_shrunk = 0;
for (x = 0; x < mb_count; x++) {
mb = &s->mb[x];
// it is OK to move blocks to ENC_SKIP here
// but not to any codebook encoding!
score1 = s->lambda * 1 + FF_LAMBDA_SCALE * mb->skip_error;
if (mb->best_encoding == ENC_SKIP) {
ret += score1;
} else if (mb->best_encoding == ENC_V1) {
if ((score2 = s->lambda * 10 + FF_LAMBDA_SCALE * mb->v1_error) >= score1) {
mb->best_encoding = ENC_SKIP;
++v1_shrunk;
ret += score1;
} else {
ret += score2;
}
} else {
if ((score3 = s->lambda * 34 + FF_LAMBDA_SCALE * mb->v4_error) >= score1) {
mb->best_encoding = ENC_SKIP;
++v4_shrunk;
ret += score1;
} else {
ret += score3;
}
}
}
*training_set_v1_shrunk = v1_shrunk;
*training_set_v4_shrunk = v4_shrunk;
} else { // find best mode per block
for (x = 0; x < mb_count; x++) {
mb = &s->mb[x];
score1 = s->lambda * 1 + FF_LAMBDA_SCALE * mb->skip_error;
score2 = s->lambda * 10 + FF_LAMBDA_SCALE * mb->v1_error;
score3 = s->lambda * 34 + FF_LAMBDA_SCALE * mb->v4_error;
if (score1 <= score2 && score1 <= score3) {
ret += score1;
mb->best_encoding = ENC_SKIP;
} else if (score2 <= score3) {
ret += score2;
mb->best_encoding = ENC_V1;
} else {
ret += score3;
mb->best_encoding = ENC_V4;
}
}
}
break;
}
return ret;
}
static int write_chunk_header(unsigned char *buf, int chunk_type, int chunk_size)
{
buf[0] = chunk_type;
AV_WB24(&buf[1], chunk_size + CHUNK_HEADER_SIZE);
return CHUNK_HEADER_SIZE;
}
static int encode_codebook(CinepakEncContext *s, int *codebook, int size,
int chunk_type_yuv, int chunk_type_gray,
unsigned char *buf)
{
int x, y, ret, entry_size = s->pix_fmt == AV_PIX_FMT_RGB24 ? 6 : 4;
int incremental_codebook_replacement_mode = 0; // hardcoded here,
// the compiler should notice that this is a constant -- rl
ret = write_chunk_header(buf,
s->pix_fmt == AV_PIX_FMT_RGB24 ?
chunk_type_yuv + (incremental_codebook_replacement_mode ? 1 : 0) :
chunk_type_gray + (incremental_codebook_replacement_mode ? 1 : 0),
entry_size * size +
(incremental_codebook_replacement_mode ? (size + 31) / 32 * 4 : 0));
// we do codebook encoding according to the "intra" mode
// but we keep the "dead" code for reference in case we will want
// to use incremental codebook updates (which actually would give us
// "kind of" motion compensation, especially in 1 strip/frame case) -- rl
// (of course, the code will be not useful as-is)
if (incremental_codebook_replacement_mode) {
int flags = 0;
int flagsind;
for (x = 0; x < size; x++) {
if (flags == 0) {
flagsind = ret;
ret += 4;
flags = 0x80000000;
} else
flags = ((flags >> 1) | 0x80000000);
for (y = 0; y < entry_size; y++)
buf[ret++] = codebook[y + x * entry_size] ^ (y >= 4 ? 0x80 : 0);
if ((flags & 0xffffffff) == 0xffffffff) {
AV_WB32(&buf[flagsind], flags);
flags = 0;
}
}
if (flags)
AV_WB32(&buf[flagsind], flags);
} else
for (x = 0; x < size; x++)
for (y = 0; y < entry_size; y++)
buf[ret++] = codebook[y + x * entry_size] ^ (y >= 4 ? 0x80 : 0);
return ret;
}
// sets out to the sub picture starting at (x,y) in in
static void get_sub_picture(CinepakEncContext *s, int x, int y,
uint8_t * in_data[4], int in_linesize[4],
uint8_t *out_data[4], int out_linesize[4])
{
out_data[0] = in_data[0] + x + y * in_linesize[0];
out_linesize[0] = in_linesize[0];
if (s->pix_fmt == AV_PIX_FMT_RGB24) {
out_data[1] = in_data[1] + (x >> 1) + (y >> 1) * in_linesize[1];
out_linesize[1] = in_linesize[1];
out_data[2] = in_data[2] + (x >> 1) + (y >> 1) * in_linesize[2];
out_linesize[2] = in_linesize[2];
}
}
// decodes the V1 vector in mb into the 4x4 MB pointed to by data
static void decode_v1_vector(CinepakEncContext *s, uint8_t *data[4],
int linesize[4], int v1_vector, strip_info *info)
{
int entry_size = s->pix_fmt == AV_PIX_FMT_RGB24 ? 6 : 4;
data[0][0] =
data[0][1] =
data[0][ linesize[0]] =
data[0][1 + linesize[0]] = info->v1_codebook[v1_vector * entry_size];
data[0][2] =
data[0][3] =
data[0][2 + linesize[0]] =
data[0][3 + linesize[0]] = info->v1_codebook[v1_vector * entry_size + 1];
data[0][ 2 * linesize[0]] =
data[0][1 + 2 * linesize[0]] =
data[0][ 3 * linesize[0]] =
data[0][1 + 3 * linesize[0]] = info->v1_codebook[v1_vector * entry_size + 2];
data[0][2 + 2 * linesize[0]] =
data[0][3 + 2 * linesize[0]] =
data[0][2 + 3 * linesize[0]] =
data[0][3 + 3 * linesize[0]] = info->v1_codebook[v1_vector * entry_size + 3];
if (s->pix_fmt == AV_PIX_FMT_RGB24) {
data[1][0] =
data[1][1] =
data[1][ linesize[1]] =
data[1][1 + linesize[1]] = info->v1_codebook[v1_vector * entry_size + 4];
data[2][0] =
data[2][1] =
data[2][ linesize[2]] =
data[2][1 + linesize[2]] = info->v1_codebook[v1_vector * entry_size + 5];
}
}
// decodes the V4 vectors in mb into the 4x4 MB pointed to by data
static void decode_v4_vector(CinepakEncContext *s, uint8_t *data[4],
int linesize[4], int *v4_vector, strip_info *info)
{
int i, x, y, entry_size = s->pix_fmt == AV_PIX_FMT_RGB24 ? 6 : 4;
for (i = y = 0; y < 4; y += 2) {
for (x = 0; x < 4; x += 2, i++) {
data[0][x + y * linesize[0]] = info->v4_codebook[v4_vector[i] * entry_size];
data[0][x + 1 + y * linesize[0]] = info->v4_codebook[v4_vector[i] * entry_size + 1];
data[0][x + (y + 1) * linesize[0]] = info->v4_codebook[v4_vector[i] * entry_size + 2];
data[0][x + 1 + (y + 1) * linesize[0]] = info->v4_codebook[v4_vector[i] * entry_size + 3];
if (s->pix_fmt == AV_PIX_FMT_RGB24) {
data[1][(x >> 1) + (y >> 1) * linesize[1]] = info->v4_codebook[v4_vector[i] * entry_size + 4];
data[2][(x >> 1) + (y >> 1) * linesize[2]] = info->v4_codebook[v4_vector[i] * entry_size + 5];
}
}
}
}
static void copy_mb(CinepakEncContext *s,
uint8_t *a_data[4], int a_linesize[4],
uint8_t *b_data[4], int b_linesize[4])
{
int y, p;
for (y = 0; y < MB_SIZE; y++)
memcpy(a_data[0] + y * a_linesize[0], b_data[0] + y * b_linesize[0],
MB_SIZE);
if (s->pix_fmt == AV_PIX_FMT_RGB24) {
for (p = 1; p <= 2; p++)
for (y = 0; y < MB_SIZE / 2; y++)
memcpy(a_data[p] + y * a_linesize[p],
b_data[p] + y * b_linesize[p],
MB_SIZE / 2);
}
}
static int encode_mode(CinepakEncContext *s, int h,
uint8_t *scratch_data[4], int scratch_linesize[4],
uint8_t *last_data[4], int last_linesize[4],
strip_info *info, unsigned char *buf)
{
int x, y, z, bits, temp_size, header_ofs, ret = 0, mb_count = s->w * h / MB_AREA;
int needs_extra_bit, should_write_temp;
uint32_t flags;
unsigned char temp[64]; // 32/2 = 16 V4 blocks at 4 B each -> 64 B
mb_info *mb;
uint8_t *sub_scratch_data[4] = { 0 }, *sub_last_data[4] = { 0 };
int sub_scratch_linesize[4] = { 0 }, sub_last_linesize[4] = { 0 };
// encode codebooks
////// MacOS vintage decoder compatibility dictates the presence of
////// the codebook chunk even when the codebook is empty - pretty dumb...
////// and also the certain order of the codebook chunks -- rl
if (info->v4_size || !s->skip_empty_cb)
ret += encode_codebook(s, info->v4_codebook, info->v4_size, 0x20, 0x24, buf + ret);
if (info->v1_size || !s->skip_empty_cb)
ret += encode_codebook(s, info->v1_codebook, info->v1_size, 0x22, 0x26, buf + ret);
// update scratch picture
for (z = y = 0; y < h; y += MB_SIZE)
for (x = 0; x < s->w; x += MB_SIZE, z++) {
mb = &s->mb[z];
get_sub_picture(s, x, y, scratch_data, scratch_linesize,
sub_scratch_data, sub_scratch_linesize);
if (info->mode == MODE_MC && mb->best_encoding == ENC_SKIP) {
get_sub_picture(s, x, y, last_data, last_linesize,
sub_last_data, sub_last_linesize);
copy_mb(s, sub_scratch_data, sub_scratch_linesize,
sub_last_data, sub_last_linesize);
} else if (info->mode == MODE_V1_ONLY || mb->best_encoding == ENC_V1)
decode_v1_vector(s, sub_scratch_data, sub_scratch_linesize,
mb->v1_vector, info);
else
decode_v4_vector(s, sub_scratch_data, sub_scratch_linesize,
mb->v4_vector, info);
}
switch (info->mode) {
case MODE_V1_ONLY:
ret += write_chunk_header(buf + ret, 0x32, mb_count);
for (x = 0; x < mb_count; x++)
buf[ret++] = s->mb[x].v1_vector;
break;
case MODE_V1_V4:
// remember header position
header_ofs = ret;
ret += CHUNK_HEADER_SIZE;
for (x = 0; x < mb_count; x += 32) {
flags = 0;
for (y = x; y < FFMIN(x + 32, mb_count); y++)
if (s->mb[y].best_encoding == ENC_V4)
flags |= 1U << (31 - y + x);
AV_WB32(&buf[ret], flags);
ret += 4;
for (y = x; y < FFMIN(x + 32, mb_count); y++) {
mb = &s->mb[y];
if (mb->best_encoding == ENC_V1)
buf[ret++] = mb->v1_vector;
else
for (z = 0; z < 4; z++)
buf[ret++] = mb->v4_vector[z];
}
}
write_chunk_header(buf + header_ofs, 0x30, ret - header_ofs - CHUNK_HEADER_SIZE);
break;
case MODE_MC:
// remember header position
header_ofs = ret;
ret += CHUNK_HEADER_SIZE;
flags = bits = temp_size = 0;
for (x = 0; x < mb_count; x++) {
mb = &s->mb[x];
flags |= (uint32_t)(mb->best_encoding != ENC_SKIP) << (31 - bits++);
needs_extra_bit = 0;
should_write_temp = 0;
if (mb->best_encoding != ENC_SKIP) {
if (bits < 32)
flags |= (uint32_t)(mb->best_encoding == ENC_V4) << (31 - bits++);
else
needs_extra_bit = 1;
}
if (bits == 32) {
AV_WB32(&buf[ret], flags);
ret += 4;
flags = bits = 0;
if (mb->best_encoding == ENC_SKIP || needs_extra_bit) {
memcpy(&buf[ret], temp, temp_size);
ret += temp_size;
temp_size = 0;
} else
should_write_temp = 1;
}
if (needs_extra_bit) {
flags = (uint32_t)(mb->best_encoding == ENC_V4) << 31;
bits = 1;
}
if (mb->best_encoding == ENC_V1)
temp[temp_size++] = mb->v1_vector;
else if (mb->best_encoding == ENC_V4)
for (z = 0; z < 4; z++)
temp[temp_size++] = mb->v4_vector[z];
if (should_write_temp) {
memcpy(&buf[ret], temp, temp_size);
ret += temp_size;
temp_size = 0;
}
}
if (bits > 0) {
AV_WB32(&buf[ret], flags);
ret += 4;
memcpy(&buf[ret], temp, temp_size);
ret += temp_size;
}
write_chunk_header(buf + header_ofs, 0x31, ret - header_ofs - CHUNK_HEADER_SIZE);
break;
}
return ret;
}
// computes distortion of 4x4 MB in b compared to a
static int compute_mb_distortion(CinepakEncContext *s,
uint8_t *a_data[4], int a_linesize[4],
uint8_t *b_data[4], int b_linesize[4])
{
int x, y, p, d, ret = 0;
for (y = 0; y < MB_SIZE; y++)
for (x = 0; x < MB_SIZE; x++) {
d = a_data[0][x + y * a_linesize[0]] - b_data[0][x + y * b_linesize[0]];
ret += d * d;
}
if (s->pix_fmt == AV_PIX_FMT_RGB24) {
for (p = 1; p <= 2; p++) {
for (y = 0; y < MB_SIZE / 2; y++)
for (x = 0; x < MB_SIZE / 2; x++) {
d = a_data[p][x + y * a_linesize[p]] - b_data[p][x + y * b_linesize[p]];
ret += d * d;
}
}
}
return ret;
}
// return the possibly adjusted size of the codebook
#define CERTAIN(x) ((x) != ENC_UNCERTAIN)
static int quantize(CinepakEncContext *s, int h, uint8_t *data[4],
int linesize[4], int v1mode, strip_info *info,
mb_encoding encoding)
{
int x, y, i, j, k, x2, y2, x3, y3, plane, shift, mbn;
int entry_size = s->pix_fmt == AV_PIX_FMT_RGB24 ? 6 : 4;
int *codebook = v1mode ? info->v1_codebook : info->v4_codebook;
int size = v1mode ? info->v1_size : info->v4_size;
int64_t total_error = 0;
uint8_t vq_pict_buf[(MB_AREA * 3) / 2];
uint8_t *sub_data[4], *vq_data[4];
int sub_linesize[4], vq_linesize[4];
for (mbn = i = y = 0; y < h; y += MB_SIZE) {
for (x = 0; x < s->w; x += MB_SIZE, ++mbn) {
int *base;
if (CERTAIN(encoding)) {
// use for the training only the blocks known to be to be encoded [sic:-]
if (s->mb[mbn].best_encoding != encoding)
continue;
}
base = s->codebook_input + i * entry_size;
if (v1mode) {
// subsample
for (j = y2 = 0; y2 < entry_size; y2 += 2)
for (x2 = 0; x2 < 4; x2 += 2, j++) {
plane = y2 < 4 ? 0 : 1 + (x2 >> 1);
shift = y2 < 4 ? 0 : 1;
x3 = shift ? 0 : x2;
y3 = shift ? 0 : y2;
base[j] = (data[plane][((x + x3) >> shift) + ((y + y3) >> shift) * linesize[plane]] +
data[plane][((x + x3) >> shift) + 1 + ((y + y3) >> shift) * linesize[plane]] +
data[plane][((x + x3) >> shift) + (((y + y3) >> shift) + 1) * linesize[plane]] +
data[plane][((x + x3) >> shift) + 1 + (((y + y3) >> shift) + 1) * linesize[plane]]) >> 2;
}
} else {
// copy
for (j = y2 = 0; y2 < MB_SIZE; y2 += 2) {
for (x2 = 0; x2 < MB_SIZE; x2 += 2)
for (k = 0; k < entry_size; k++, j++) {
plane = k >= 4 ? k - 3 : 0;
if (k >= 4) {
x3 = (x + x2) >> 1;
y3 = (y + y2) >> 1;
} else {
x3 = x + x2 + (k & 1);
y3 = y + y2 + (k >> 1);
}
base[j] = data[plane][x3 + y3 * linesize[plane]];
}
}
}
i += v1mode ? 1 : 4;
}
}
if (i == 0) // empty training set, nothing to do
return 0;
if (i < size)
size = i;
avpriv_init_elbg(s->codebook_input, entry_size, i, codebook, size, 1, s->codebook_closest, &s->randctx);
avpriv_do_elbg(s->codebook_input, entry_size, i, codebook, size, 1, s->codebook_closest, &s->randctx);
// set up vq_data, which contains a single MB
vq_data[0] = vq_pict_buf;
vq_linesize[0] = MB_SIZE;
vq_data[1] = &vq_pict_buf[MB_AREA];
vq_data[2] = vq_data[1] + (MB_AREA >> 2);
vq_linesize[1] =
vq_linesize[2] = MB_SIZE >> 1;
// copy indices
for (i = j = y = 0; y < h; y += MB_SIZE)
for (x = 0; x < s->w; x += MB_SIZE, j++) {
mb_info *mb = &s->mb[j];
// skip uninteresting blocks if we know their preferred encoding
if (CERTAIN(encoding) && mb->best_encoding != encoding)
continue;
// point sub_data to current MB
get_sub_picture(s, x, y, data, linesize, sub_data, sub_linesize);
if (v1mode) {
mb->v1_vector = s->codebook_closest[i];
// fill in vq_data with V1 data
decode_v1_vector(s, vq_data, vq_linesize, mb->v1_vector, info);
mb->v1_error = compute_mb_distortion(s, sub_data, sub_linesize,
vq_data, vq_linesize);
total_error += mb->v1_error;
} else {
for (k = 0; k < 4; k++)
mb->v4_vector[k] = s->codebook_closest[i + k];
// fill in vq_data with V4 data
decode_v4_vector(s, vq_data, vq_linesize, mb->v4_vector, info);
mb->v4_error = compute_mb_distortion(s, sub_data, sub_linesize,
vq_data, vq_linesize);
total_error += mb->v4_error;
}
i += v1mode ? 1 : 4;
}
// check that we did it right in the beginning of the function
av_assert0(i >= size); // training set is no smaller than the codebook
return size;
}
static void calculate_skip_errors(CinepakEncContext *s, int h,
uint8_t *last_data[4], int last_linesize[4],
uint8_t *data[4], int linesize[4],
strip_info *info)
{
int x, y, i;
uint8_t *sub_last_data [4], *sub_pict_data [4];
int sub_last_linesize[4], sub_pict_linesize[4];
for (i = y = 0; y < h; y += MB_SIZE)
for (x = 0; x < s->w; x += MB_SIZE, i++) {
get_sub_picture(s, x, y, last_data, last_linesize,
sub_last_data, sub_last_linesize);
get_sub_picture(s, x, y, data, linesize,
sub_pict_data, sub_pict_linesize);
s->mb[i].skip_error =
compute_mb_distortion(s,
sub_last_data, sub_last_linesize,
sub_pict_data, sub_pict_linesize);
}
}
static void write_strip_header(CinepakEncContext *s, int y, int h, int keyframe,
unsigned char *buf, int strip_size)
{
// actually we are exclusively using intra strip coding (how much can we win
// otherwise? how to choose which part of a codebook to update?),
// keyframes are different only because we disallow ENC_SKIP on them -- rl
// (besides, the logic here used to be inverted: )
// buf[0] = keyframe ? 0x11: 0x10;
buf[0] = keyframe ? 0x10 : 0x11;
AV_WB24(&buf[1], strip_size + STRIP_HEADER_SIZE);
// AV_WB16(&buf[4], y); /* using absolute y values works -- rl */
AV_WB16(&buf[4], 0); /* using relative values works as well -- rl */
AV_WB16(&buf[6], 0);
// AV_WB16(&buf[8], y + h); /* using absolute y values works -- rl */
AV_WB16(&buf[8], h); /* using relative values works as well -- rl */
AV_WB16(&buf[10], s->w);
}
static int rd_strip(CinepakEncContext *s, int y, int h, int keyframe,
uint8_t *last_data[4], int last_linesize[4],
uint8_t *data[4], int linesize[4],
uint8_t *scratch_data[4], int scratch_linesize[4],
unsigned char *buf, int64_t *best_score)
{
int64_t score = 0;
int best_size = 0;
strip_info info;
// for codebook optimization:
int v1enough, v1_size, v4enough, v4_size;
int new_v1_size, new_v4_size;
int v1shrunk, v4shrunk;
if (!keyframe)
calculate_skip_errors(s, h, last_data, last_linesize, data, linesize,
&info);
// try some powers of 4 for the size of the codebooks
// constraint the v4 codebook to be no bigger than v1 one,
// (and no less than v1_size/4)
// thus making v1 preferable and possibly losing small details? should be ok
#define SMALLEST_CODEBOOK 1
for (v1enough = 0, v1_size = SMALLEST_CODEBOOK; v1_size <= CODEBOOK_MAX && !v1enough; v1_size <<= 2) {
for (v4enough = 0, v4_size = 0; v4_size <= v1_size && !v4enough; v4_size = v4_size ? v4_size << 2 : v1_size >= SMALLEST_CODEBOOK << 2 ? v1_size >> 2 : SMALLEST_CODEBOOK) {
CinepakMode mode;
// try all modes
for (mode = 0; mode < MODE_COUNT; mode++) {
// don't allow MODE_MC in intra frames
if (keyframe && mode == MODE_MC)
continue;
if (mode == MODE_V1_ONLY) {
info.v1_size = v1_size;
// the size may shrink even before optimizations if the input is short:
info.v1_size = quantize(s, h, data, linesize, 1,
&info, ENC_UNCERTAIN);
if (info.v1_size < v1_size)
// too few eligible blocks, no sense in trying bigger sizes
v1enough = 1;
info.v4_size = 0;
} else { // mode != MODE_V1_ONLY
// if v4 codebook is empty then only allow V1-only mode
if (!v4_size)
continue;
if (mode == MODE_V1_V4) {
info.v4_size = v4_size;
info.v4_size = quantize(s, h, data, linesize, 0,
&info, ENC_UNCERTAIN);
if (info.v4_size < v4_size)
// too few eligible blocks, no sense in trying bigger sizes
v4enough = 1;
}
}
info.mode = mode;
// choose the best encoding per block, based on current experience
score = calculate_mode_score(s, h, &info, 0,
&v1shrunk, &v4shrunk);
if (mode != MODE_V1_ONLY) {
int extra_iterations_limit = s->max_extra_cb_iterations;
// recompute the codebooks, omitting the extra blocks
// we assume we _may_ come here with more blocks to encode than before
info.v1_size = v1_size;
new_v1_size = quantize(s, h, data, linesize, 1, &info, ENC_V1);
if (new_v1_size < info.v1_size)
info.v1_size = new_v1_size;
// we assume we _may_ come here with more blocks to encode than before
info.v4_size = v4_size;
new_v4_size = quantize(s, h, data, linesize, 0, &info, ENC_V4);
if (new_v4_size < info.v4_size)
info.v4_size = new_v4_size;
// calculate the resulting score
// (do not move blocks to codebook encodings now, as some blocks may have
// got bigger errors despite a smaller training set - but we do not
// ever grow the training sets back)
for (;;) {
score = calculate_mode_score(s, h, &info, 1,
&v1shrunk, &v4shrunk);
// do we have a reason to reiterate? if so, have we reached the limit?
if ((!v1shrunk && !v4shrunk) || !extra_iterations_limit--)
break;
// recompute the codebooks, omitting the extra blocks
if (v1shrunk) {
info.v1_size = v1_size;
new_v1_size = quantize(s, h, data, linesize, 1, &info, ENC_V1);
if (new_v1_size < info.v1_size)
info.v1_size = new_v1_size;
}
if (v4shrunk) {
info.v4_size = v4_size;
new_v4_size = quantize(s, h, data, linesize, 0, &info, ENC_V4);
if (new_v4_size < info.v4_size)
info.v4_size = new_v4_size;
}
}
}
if (best_size == 0 || score < *best_score) {
*best_score = score;
best_size = encode_mode(s, h,
scratch_data, scratch_linesize,
last_data, last_linesize, &info,
s->strip_buf + STRIP_HEADER_SIZE);
write_strip_header(s, y, h, keyframe, s->strip_buf, best_size);
}
}
}
}
best_size += STRIP_HEADER_SIZE;
memcpy(buf, s->strip_buf, best_size);
return best_size;
}
static int write_cvid_header(CinepakEncContext *s, unsigned char *buf,
int num_strips, int data_size, int isakeyframe)
{
buf[0] = isakeyframe ? 0 : 1;
AV_WB24(&buf[1], data_size + CVID_HEADER_SIZE);
AV_WB16(&buf[4], s->w);
AV_WB16(&buf[6], s->h);
AV_WB16(&buf[8], num_strips);
return CVID_HEADER_SIZE;
}
static int rd_frame(CinepakEncContext *s, const AVFrame *frame,
int isakeyframe, unsigned char *buf, int buf_size)
{
int num_strips, strip, i, y, nexty, size, temp_size, best_size;
uint8_t *last_data [4], *data [4], *scratch_data [4];
int last_linesize[4], linesize[4], scratch_linesize[4];
int64_t best_score = 0, score, score_temp;
int best_nstrips;
if (s->pix_fmt == AV_PIX_FMT_RGB24) {
int x;
// build a copy of the given frame in the correct colorspace
for (y = 0; y < s->h; y += 2)
for (x = 0; x < s->w; x += 2) {
uint8_t *ir[2];
int32_t r, g, b, rr, gg, bb;
ir[0] = frame->data[0] + x * 3 + y * frame->linesize[0];
ir[1] = ir[0] + frame->linesize[0];
get_sub_picture(s, x, y,
s->input_frame->data, s->input_frame->linesize,
scratch_data, scratch_linesize);
r = g = b = 0;
for (i = 0; i < 4; ++i) {
int i1, i2;
i1 = (i & 1);
i2 = (i >= 2);
rr = ir[i2][i1 * 3 + 0];
gg = ir[i2][i1 * 3 + 1];
bb = ir[i2][i1 * 3 + 2];
r += rr;
g += gg;
b += bb;
// using fixed point arithmetic for portable repeatability, scaling by 2^23
// "Y"
// rr = 0.2857 * rr + 0.5714 * gg + 0.1429 * bb;
rr = (2396625 * rr + 4793251 * gg + 1198732 * bb) >> 23;
if (rr < 0)
rr = 0;
else if (rr > 255)
rr = 255;
scratch_data[0][i1 + i2 * scratch_linesize[0]] = rr;
}
// let us scale down as late as possible
// r /= 4; g /= 4; b /= 4;
// "U"
// rr = -0.1429 * r - 0.2857 * g + 0.4286 * b;
rr = (-299683 * r - 599156 * g + 898839 * b) >> 23;
if (rr < -128)
rr = -128;
else if (rr > 127)
rr = 127;
scratch_data[1][0] = rr + 128; // quantize needs unsigned
// "V"
// rr = 0.3571 * r - 0.2857 * g - 0.0714 * b;
rr = (748893 * r - 599156 * g - 149737 * b) >> 23;
if (rr < -128)
rr = -128;
else if (rr > 127)
rr = 127;
scratch_data[2][0] = rr + 128; // quantize needs unsigned
}
}
// would be nice but quite certainly incompatible with vintage players:
// support encoding zero strips (meaning skip the whole frame)
for (num_strips = s->min_strips; num_strips <= s->max_strips && num_strips <= s->h / MB_SIZE; num_strips++) {
score = 0;
size = 0;
for (y = 0, strip = 1; y < s->h; strip++, y = nexty) {
int strip_height;
nexty = strip * s->h / num_strips; // <= s->h
// make nexty the next multiple of 4 if not already there
if (nexty & 3)
nexty += 4 - (nexty & 3);
strip_height = nexty - y;
if (strip_height <= 0) { // can this ever happen?
av_log(s->avctx, AV_LOG_INFO, "skipping zero height strip %i of %i\n", strip, num_strips);
continue;
}
if (s->pix_fmt == AV_PIX_FMT_RGB24)
get_sub_picture(s, 0, y,
s->input_frame->data, s->input_frame->linesize,
data, linesize);
else
get_sub_picture(s, 0, y,
(uint8_t **)frame->data, (int *)frame->linesize,
data, linesize);
get_sub_picture(s, 0, y,
s->last_frame->data, s->last_frame->linesize,
last_data, last_linesize);
get_sub_picture(s, 0, y,
s->scratch_frame->data, s->scratch_frame->linesize,
scratch_data, scratch_linesize);
if ((temp_size = rd_strip(s, y, strip_height, isakeyframe,
last_data, last_linesize, data, linesize,
scratch_data, scratch_linesize,
s->frame_buf + size + CVID_HEADER_SIZE,
&score_temp)) < 0)
return temp_size;
score += score_temp;
size += temp_size;
}
if (best_score == 0 || score < best_score) {
best_score = score;
best_size = size + write_cvid_header(s, s->frame_buf, num_strips, size, isakeyframe);
FFSWAP(AVFrame *, s->best_frame, s->scratch_frame);
memcpy(buf, s->frame_buf, best_size);
best_nstrips = num_strips;
}
// avoid trying too many strip numbers without a real reason
// (this makes the processing of the very first frame faster)
if (num_strips - best_nstrips > 4)
break;
}
// let the number of strips slowly adapt to the changes in the contents,
// compared to full bruteforcing every time this will occasionally lead
// to some r/d performance loss but makes encoding up to several times faster
if (!s->strip_number_delta_range) {
if (best_nstrips == s->max_strips) { // let us try to step up
s->max_strips = best_nstrips + 1;
if (s->max_strips >= s->max_max_strips)
s->max_strips = s->max_max_strips;
} else { // try to step down
s->max_strips = best_nstrips;
}
s->min_strips = s->max_strips - 1;
if (s->min_strips < s->min_min_strips)
s->min_strips = s->min_min_strips;
} else {
s->max_strips = best_nstrips + s->strip_number_delta_range;
if (s->max_strips >= s->max_max_strips)
s->max_strips = s->max_max_strips;
s->min_strips = best_nstrips - s->strip_number_delta_range;
if (s->min_strips < s->min_min_strips)
s->min_strips = s->min_min_strips;
}
return best_size;
}
static int cinepak_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
const AVFrame *frame, int *got_packet)
{
CinepakEncContext *s = avctx->priv_data;
int ret;
s->lambda = frame->quality ? frame->quality - 1 : 2 * FF_LAMBDA_SCALE;
if ((ret = ff_alloc_packet2(avctx, pkt, s->frame_buf_size, 0)) < 0)
return ret;
ret = rd_frame(s, frame, (s->curframe == 0), pkt->data, s->frame_buf_size);
pkt->size = ret;
if (s->curframe == 0)
pkt->flags |= AV_PKT_FLAG_KEY;
*got_packet = 1;
FFSWAP(AVFrame *, s->last_frame, s->best_frame);
if (++s->curframe >= s->keyint)
s->curframe = 0;
return 0;
}
static av_cold int cinepak_encode_end(AVCodecContext *avctx)
{
CinepakEncContext *s = avctx->priv_data;
int x;
av_frame_free(&s->last_frame);
av_frame_free(&s->best_frame);
av_frame_free(&s->scratch_frame);
if (avctx->pix_fmt == AV_PIX_FMT_RGB24)
av_frame_free(&s->input_frame);
av_freep(&s->codebook_input);
av_freep(&s->codebook_closest);
av_freep(&s->strip_buf);
av_freep(&s->frame_buf);
av_freep(&s->mb);
for (x = 0; x < (avctx->pix_fmt == AV_PIX_FMT_RGB24 ? 4 : 3); x++)
av_freep(&s->pict_bufs[x]);
return 0;
}
AVCodec ff_cinepak_encoder = {
.name = "cinepak",
.long_name = NULL_IF_CONFIG_SMALL("Cinepak"),
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_CINEPAK,
.priv_data_size = sizeof(CinepakEncContext),
.init = cinepak_encode_init,
.encode2 = cinepak_encode_frame,
.close = cinepak_encode_end,
.pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_RGB24, AV_PIX_FMT_GRAY8, AV_PIX_FMT_NONE },
.priv_class = &cinepak_class,
};