ffmpeg/libavcodec/rpzaenc.c

885 lines
28 KiB
C

/*
* QuickTime RPZA Video Encoder
*
* 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 rpzaenc.c
* QT RPZA Video Encoder by Todd Kirby <doubleshot@pacbell.net> and David Adler
*/
#include "libavutil/avassert.h"
#include "libavutil/common.h"
#include "libavutil/opt.h"
#include "avcodec.h"
#include "codec_internal.h"
#include "encode.h"
#include "put_bits.h"
typedef struct RpzaContext {
AVClass *avclass;
int skip_frame_thresh;
int start_one_color_thresh;
int continue_one_color_thresh;
int sixteen_color_thresh;
AVFrame *prev_frame; // buffer for previous source frame
PutBitContext pb; // buffer for encoded frame data.
int frame_width; // width in pixels of source frame
int frame_height; // height in pixesl of source frame
int first_frame; // flag set to one when the first frame is being processed
// so that comparisons with previous frame data in not attempted
} RpzaContext;
typedef enum channel_offset {
RED = 2,
GREEN = 1,
BLUE = 0,
} channel_offset;
typedef struct rgb {
uint8_t r;
uint8_t g;
uint8_t b;
} rgb;
#define SQR(x) ((x) * (x))
/* 15 bit components */
#define GET_CHAN(color, chan) (((color) >> ((chan) * 5) & 0x1F) * 8)
#define R(color) GET_CHAN(color, RED)
#define G(color) GET_CHAN(color, GREEN)
#define B(color) GET_CHAN(color, BLUE)
typedef struct BlockInfo {
int row;
int col;
int block_width;
int block_height;
int image_width;
int image_height;
int block_index;
uint16_t start;
int rowstride;
int prev_rowstride;
int blocks_per_row;
int total_blocks;
} BlockInfo;
static void get_colors(const uint8_t *min, const uint8_t *max, uint8_t color4[4][3])
{
uint8_t step;
color4[0][0] = min[0];
color4[0][1] = min[1];
color4[0][2] = min[2];
color4[3][0] = max[0];
color4[3][1] = max[1];
color4[3][2] = max[2];
// red components
step = (color4[3][0] - color4[0][0] + 1) / 3;
color4[1][0] = color4[0][0] + step;
color4[2][0] = color4[3][0] - step;
// green components
step = (color4[3][1] - color4[0][1] + 1) / 3;
color4[1][1] = color4[0][1] + step;
color4[2][1] = color4[3][1] - step;
// blue components
step = (color4[3][2] - color4[0][2] + 1) / 3;
color4[1][2] = color4[0][2] + step;
color4[2][2] = color4[3][2] - step;
}
/* Fill BlockInfo struct with information about a 4x4 block of the image */
static int get_block_info(BlockInfo *bi, int block, int prev_frame)
{
bi->row = block / bi->blocks_per_row;
bi->col = block % bi->blocks_per_row;
// test for right edge block
if (bi->col == bi->blocks_per_row - 1 && (bi->image_width % 4) != 0) {
bi->block_width = bi->image_width % 4;
} else {
bi->block_width = 4;
}
// test for bottom edge block
if (bi->row == (bi->image_height / 4) && (bi->image_height % 4) != 0) {
bi->block_height = bi->image_height % 4;
} else {
bi->block_height = 4;
}
return block ? (bi->col * 4) + (bi->row * (prev_frame ? bi->prev_rowstride : bi->rowstride) * 4) : 0;
}
static uint16_t rgb24_to_rgb555(const uint8_t *rgb24)
{
uint16_t rgb555 = 0;
uint32_t r, g, b;
r = rgb24[0] >> 3;
g = rgb24[1] >> 3;
b = rgb24[2] >> 3;
rgb555 |= (r << 10);
rgb555 |= (g << 5);
rgb555 |= (b << 0);
return rgb555;
}
/*
* Returns the total difference between two 24 bit color values
*/
static int diff_colors(const uint8_t *colorA, const uint8_t *colorB)
{
int tot;
tot = SQR(colorA[0] - colorB[0]);
tot += SQR(colorA[1] - colorB[1]);
tot += SQR(colorA[2] - colorB[2]);
return tot;
}
/*
* Returns the maximum channel difference
*/
static int max_component_diff(const uint16_t *colorA, const uint16_t *colorB)
{
int diff, max = 0;
diff = FFABS(R(colorA[0]) - R(colorB[0]));
if (diff > max) {
max = diff;
}
diff = FFABS(G(colorA[0]) - G(colorB[0]));
if (diff > max) {
max = diff;
}
diff = FFABS(B(colorA[0]) - B(colorB[0]));
if (diff > max) {
max = diff;
}
return max * 8;
}
/*
* Find the channel that has the largest difference between minimum and maximum
* color values. Put the minimum value in min, maximum in max and the channel
* in chan.
*/
static void get_max_component_diff(const BlockInfo *bi, const uint16_t *block_ptr,
uint8_t *min, uint8_t *max, channel_offset *chan)
{
int x, y;
uint8_t min_r, max_r, min_g, max_g, min_b, max_b;
uint8_t r, g, b;
// fix warning about uninitialized vars
min_r = min_g = min_b = UINT8_MAX;
max_r = max_g = max_b = 0;
// loop thru and compare pixels
for (y = 0; y < bi->block_height; y++) {
for (x = 0; x < bi->block_width; x++) {
// TODO: optimize
min_r = FFMIN(R(block_ptr[x]), min_r);
min_g = FFMIN(G(block_ptr[x]), min_g);
min_b = FFMIN(B(block_ptr[x]), min_b);
max_r = FFMAX(R(block_ptr[x]), max_r);
max_g = FFMAX(G(block_ptr[x]), max_g);
max_b = FFMAX(B(block_ptr[x]), max_b);
}
block_ptr += bi->rowstride;
}
r = max_r - min_r;
g = max_g - min_g;
b = max_b - min_b;
if (r > g && r > b) {
*max = max_r;
*min = min_r;
*chan = RED;
} else if (g > b && g >= r) {
*max = max_g;
*min = min_g;
*chan = GREEN;
} else {
*max = max_b;
*min = min_b;
*chan = BLUE;
}
}
/*
* Compare two 4x4 blocks to determine if the total difference between the
* blocks is greater than the thresh parameter. Returns -1 if difference
* exceeds threshold or zero otherwise.
*/
static int compare_blocks(const uint16_t *block1, const uint16_t *block2,
const BlockInfo *bi, int thresh)
{
int x, y, diff = 0;
for (y = 0; y < bi->block_height; y++) {
for (x = 0; x < bi->block_width; x++) {
diff = max_component_diff(&block1[x], &block2[x]);
if (diff >= thresh) {
return -1;
}
}
block1 += bi->prev_rowstride;
block2 += bi->rowstride;
}
return 0;
}
/*
* Determine the fit of one channel to another within a 4x4 block. This
* is used to determine the best palette choices for 4-color encoding.
*/
static int leastsquares(const uint16_t *block_ptr, const BlockInfo *bi,
channel_offset xchannel, channel_offset ychannel,
double *slope, double *y_intercept, double *correlation_coef)
{
double sumx = 0, sumy = 0, sumx2 = 0, sumy2 = 0, sumxy = 0,
sumx_sq = 0, sumy_sq = 0, tmp, tmp2;
int i, j, count;
uint8_t x, y;
count = bi->block_height * bi->block_width;
if (count < 2)
return -1;
for (i = 0; i < bi->block_height; i++) {
for (j = 0; j < bi->block_width; j++) {
x = GET_CHAN(block_ptr[j], xchannel);
y = GET_CHAN(block_ptr[j], ychannel);
sumx += x;
sumy += y;
sumx2 += x * x;
sumy2 += y * y;
sumxy += x * y;
}
block_ptr += bi->rowstride;
}
sumx_sq = sumx * sumx;
tmp = (count * sumx2 - sumx_sq);
// guard against div/0
if (tmp == 0)
return -2;
sumy_sq = sumy * sumy;
*slope = (sumx * sumy - sumxy) / tmp;
*y_intercept = (sumy - (*slope) * sumx) / count;
tmp2 = count * sumy2 - sumy_sq;
if (tmp2 == 0) {
*correlation_coef = 0.0;
} else {
*correlation_coef = (count * sumxy - sumx * sumy) /
sqrt(tmp * tmp2);
}
return 0; // success
}
/*
* Determine the amount of error in the leastsquares fit.
*/
static int calc_lsq_max_fit_error(const uint16_t *block_ptr, const BlockInfo *bi,
int min, int max, int tmp_min, int tmp_max,
channel_offset xchannel, channel_offset ychannel)
{
int i, j, x, y;
int err;
int max_err = 0;
for (i = 0; i < bi->block_height; i++) {
for (j = 0; j < bi->block_width; j++) {
int x_inc, lin_y, lin_x;
x = GET_CHAN(block_ptr[j], xchannel);
y = GET_CHAN(block_ptr[j], ychannel);
/* calculate x_inc as the 4-color index (0..3) */
x_inc = floor( (x - min) * 3.0 / (max - min) + 0.5);
x_inc = FFMAX(FFMIN(3, x_inc), 0);
/* calculate lin_y corresponding to x_inc */
lin_y = (int)(tmp_min + (tmp_max - tmp_min) * x_inc / 3.0 + 0.5);
err = FFABS(lin_y - y);
if (err > max_err)
max_err = err;
/* calculate lin_x corresponding to x_inc */
lin_x = (int)(min + (max - min) * x_inc / 3.0 + 0.5);
err = FFABS(lin_x - x);
if (err > max_err)
max_err += err;
}
block_ptr += bi->rowstride;
}
return max_err;
}
/*
* Find the closest match to a color within the 4-color palette
*/
static int match_color(const uint16_t *color, uint8_t colors[4][3])
{
int ret = 0;
int smallest_variance = INT_MAX;
uint8_t dithered_color[3];
for (int channel = 0; channel < 3; channel++) {
dithered_color[channel] = GET_CHAN(color[0], channel);
}
for (int palette_entry = 0; palette_entry < 4; palette_entry++) {
int variance = diff_colors(dithered_color, colors[palette_entry]);
if (variance < smallest_variance) {
smallest_variance = variance;
ret = palette_entry;
}
}
return ret;
}
/*
* Encode a block using the 4-color opcode and palette. return number of
* blocks encoded (until we implement multi-block 4 color runs this will
* always be 1)
*/
static int encode_four_color_block(const uint8_t *min_color, const uint8_t *max_color,
PutBitContext *pb, const uint16_t *block_ptr, const BlockInfo *bi)
{
const int y_size = FFMIN(4, bi->image_height - bi->row * 4);
const int x_size = FFMIN(4, bi->image_width - bi->col * 4);
uint8_t color4[4][3];
uint16_t rounded_max, rounded_min;
int idx;
// round min and max wider
rounded_min = rgb24_to_rgb555(min_color);
rounded_max = rgb24_to_rgb555(max_color);
// put a and b colors
// encode 4 colors = first 16 bit color with MSB zeroed and...
put_bits(pb, 16, rounded_max & ~0x8000);
// ...second 16 bit color with MSB on.
put_bits(pb, 16, rounded_min | 0x8000);
get_colors(min_color, max_color, color4);
for (int y = 0; y < y_size; y++) {
for (int x = 0; x < x_size; x++) {
idx = match_color(&block_ptr[x], color4);
put_bits(pb, 2, idx);
}
for (int x = x_size; x < 4; x++)
put_bits(pb, 2, idx);
block_ptr += bi->rowstride;
}
for (int y = y_size; y < 4; y++) {
for (int x = 0; x < 4; x++)
put_bits(pb, 2, 0);
}
return 1; // num blocks encoded
}
/*
* Copy a 4x4 block from the current frame buffer to the previous frame buffer.
*/
static void update_block_in_prev_frame(const uint16_t *src_pixels,
uint16_t *dest_pixels,
const BlockInfo *bi, int block_counter)
{
const int y_size = FFMIN(4, bi->image_height - bi->row * 4);
const int x_size = FFMIN(4, bi->image_width - bi->col * 4) * 2;
for (int y = 0; y < y_size; y++) {
memcpy(dest_pixels, src_pixels, x_size);
dest_pixels += bi->prev_rowstride;
src_pixels += bi->rowstride;
}
}
/*
* update statistics for the specified block. If first_block,
* it initializes the statistics. Otherwise it updates the statistics IF THIS
* BLOCK IS SUITABLE TO CONTINUE A 1-COLOR RUN. That is, it checks whether
* the range of colors (since the routine was called first_block != 0) are
* all close enough intensities to be represented by a single color.
* The routine returns 0 if this block is too different to be part of
* the same run of 1-color blocks. The routine returns 1 if this
* block can be part of the same 1-color block run.
* If the routine returns 1, it also updates its arguments to include
* the statistics of this block. Otherwise, the stats are unchanged
* and don't include the current block.
*/
static int update_block_stats(RpzaContext *s, const BlockInfo *bi, const uint16_t *block,
uint8_t min_color[3], uint8_t max_color[3],
int *total_rgb, int *total_pixels,
uint8_t avg_color[3], int first_block)
{
int x, y;
int is_in_range;
int total_pixels_blk;
int threshold;
uint8_t min_color_blk[3], max_color_blk[3];
int total_rgb_blk[3];
uint8_t avg_color_blk[3];
if (first_block) {
min_color[0] = UINT8_MAX;
min_color[1] = UINT8_MAX;
min_color[2] = UINT8_MAX;
max_color[0] = 0;
max_color[1] = 0;
max_color[2] = 0;
total_rgb[0] = 0;
total_rgb[1] = 0;
total_rgb[2] = 0;
*total_pixels = 0;
threshold = s->start_one_color_thresh;
} else {
threshold = s->continue_one_color_thresh;
}
/*
The *_blk variables will include the current block.
Initialize them based on the blocks so far.
*/
min_color_blk[0] = min_color[0];
min_color_blk[1] = min_color[1];
min_color_blk[2] = min_color[2];
max_color_blk[0] = max_color[0];
max_color_blk[1] = max_color[1];
max_color_blk[2] = max_color[2];
total_rgb_blk[0] = total_rgb[0];
total_rgb_blk[1] = total_rgb[1];
total_rgb_blk[2] = total_rgb[2];
total_pixels_blk = *total_pixels + bi->block_height * bi->block_width;
/*
Update stats for this block's pixels
*/
for (y = 0; y < bi->block_height; y++) {
for (x = 0; x < bi->block_width; x++) {
total_rgb_blk[0] += R(block[x]);
total_rgb_blk[1] += G(block[x]);
total_rgb_blk[2] += B(block[x]);
min_color_blk[0] = FFMIN(R(block[x]), min_color_blk[0]);
min_color_blk[1] = FFMIN(G(block[x]), min_color_blk[1]);
min_color_blk[2] = FFMIN(B(block[x]), min_color_blk[2]);
max_color_blk[0] = FFMAX(R(block[x]), max_color_blk[0]);
max_color_blk[1] = FFMAX(G(block[x]), max_color_blk[1]);
max_color_blk[2] = FFMAX(B(block[x]), max_color_blk[2]);
}
block += bi->rowstride;
}
/*
Calculate average color including current block.
*/
avg_color_blk[0] = total_rgb_blk[0] / total_pixels_blk;
avg_color_blk[1] = total_rgb_blk[1] / total_pixels_blk;
avg_color_blk[2] = total_rgb_blk[2] / total_pixels_blk;
/*
Are all the pixels within threshold of the average color?
*/
is_in_range = (max_color_blk[0] - avg_color_blk[0] <= threshold &&
max_color_blk[1] - avg_color_blk[1] <= threshold &&
max_color_blk[2] - avg_color_blk[2] <= threshold &&
avg_color_blk[0] - min_color_blk[0] <= threshold &&
avg_color_blk[1] - min_color_blk[1] <= threshold &&
avg_color_blk[2] - min_color_blk[2] <= threshold);
if (is_in_range) {
/*
Set the output variables to include this block.
*/
min_color[0] = min_color_blk[0];
min_color[1] = min_color_blk[1];
min_color[2] = min_color_blk[2];
max_color[0] = max_color_blk[0];
max_color[1] = max_color_blk[1];
max_color[2] = max_color_blk[2];
total_rgb[0] = total_rgb_blk[0];
total_rgb[1] = total_rgb_blk[1];
total_rgb[2] = total_rgb_blk[2];
*total_pixels = total_pixels_blk;
avg_color[0] = avg_color_blk[0];
avg_color[1] = avg_color_blk[1];
avg_color[2] = avg_color_blk[2];
}
return is_in_range;
}
static void rpza_encode_stream(RpzaContext *s, const AVFrame *pict)
{
BlockInfo bi;
int block_counter = 0;
int n_blocks;
int total_blocks;
int prev_block_offset;
int block_offset = 0;
int pblock_offset = 0;
uint8_t min = 0, max = 0;
channel_offset chan;
int i;
int tmp_min, tmp_max;
int total_rgb[3];
uint8_t avg_color[3];
int pixel_count;
uint8_t min_color[3], max_color[3];
double slope, y_intercept, correlation_coef;
const uint16_t *src_pixels = (const uint16_t *)pict->data[0];
uint16_t *prev_pixels = (uint16_t *)s->prev_frame->data[0];
/* Number of 4x4 blocks in frame. */
total_blocks = ((s->frame_width + 3) / 4) * ((s->frame_height + 3) / 4);
bi.image_width = s->frame_width;
bi.image_height = s->frame_height;
bi.rowstride = pict->linesize[0] / 2;
bi.prev_rowstride = s->prev_frame->linesize[0] / 2;
bi.blocks_per_row = (s->frame_width + 3) / 4;
while (block_counter < total_blocks) {
// SKIP CHECK
// make sure we have a valid previous frame and we're not writing
// a key frame
if (!s->first_frame) {
n_blocks = 0;
prev_block_offset = 0;
while (n_blocks < 32 && block_counter + n_blocks < total_blocks) {
block_offset = get_block_info(&bi, block_counter + n_blocks, 0);
pblock_offset = get_block_info(&bi, block_counter + n_blocks, 1);
// multi-block opcodes cannot span multiple rows.
// If we're starting a new row, break out and write the opcode
/* TODO: Should eventually use bi.row here to determine when a
row break occurs, but that is currently breaking the
quicktime player. This is probably due to a bug in the
way I'm calculating the current row.
*/
if (prev_block_offset && block_offset - prev_block_offset > 12) {
break;
}
prev_block_offset = block_offset;
if (compare_blocks(&prev_pixels[pblock_offset],
&src_pixels[block_offset], &bi, s->skip_frame_thresh) != 0) {
// write out skipable blocks
if (n_blocks) {
// write skip opcode
put_bits(&s->pb, 8, 0x80 | (n_blocks - 1));
block_counter += n_blocks;
goto post_skip;
}
break;
}
/*
* NOTE: we don't update skipped blocks in the previous frame buffer
* since skipped needs always to be compared against the first skipped
* block to avoid artifacts during gradual fade in/outs.
*/
// update_block_in_prev_frame(&src_pixels[block_offset],
// &prev_pixels[pblock_offset], &bi, block_counter + n_blocks);
n_blocks++;
}
// we're either at the end of the frame or we've reached the maximum
// of 32 blocks in a run. Write out the run.
if (n_blocks) {
// write skip opcode
put_bits(&s->pb, 8, 0x80 | (n_blocks - 1));
block_counter += n_blocks;
continue;
}
} else {
block_offset = get_block_info(&bi, block_counter, 0);
pblock_offset = get_block_info(&bi, block_counter, 1);
}
post_skip :
// ONE COLOR CHECK
if (update_block_stats(s, &bi, &src_pixels[block_offset],
min_color, max_color,
total_rgb, &pixel_count, avg_color, 1)) {
prev_block_offset = block_offset;
n_blocks = 1;
/* update this block in the previous frame buffer */
update_block_in_prev_frame(&src_pixels[block_offset],
&prev_pixels[pblock_offset], &bi, block_counter + n_blocks);
// check for subsequent blocks with the same color
while (n_blocks < 32 && block_counter + n_blocks < total_blocks) {
block_offset = get_block_info(&bi, block_counter + n_blocks, 0);
pblock_offset = get_block_info(&bi, block_counter + n_blocks, 1);
// multi-block opcodes cannot span multiple rows.
// If we've hit end of a row, break out and write the opcode
if (block_offset - prev_block_offset > 12) {
break;
}
if (!update_block_stats(s, &bi, &src_pixels[block_offset],
min_color, max_color,
total_rgb, &pixel_count, avg_color, 0)) {
break;
}
prev_block_offset = block_offset;
/* update this block in the previous frame buffer */
update_block_in_prev_frame(&src_pixels[block_offset],
&prev_pixels[pblock_offset], &bi, block_counter + n_blocks);
n_blocks++;
}
// write one color opcode.
put_bits(&s->pb, 8, 0xa0 | (n_blocks - 1));
// write color to encode.
put_bits(&s->pb, 16, rgb24_to_rgb555(avg_color));
// skip past the blocks we've just encoded.
block_counter += n_blocks;
} else { // FOUR COLOR CHECK
int err = 0;
// get max component diff for block
get_max_component_diff(&bi, &src_pixels[block_offset], &min, &max, &chan);
min_color[0] = 0;
max_color[0] = 0;
min_color[1] = 0;
max_color[1] = 0;
min_color[2] = 0;
max_color[2] = 0;
// run least squares against other two components
for (i = 0; i < 3; i++) {
if (i == chan) {
min_color[i] = min;
max_color[i] = max;
continue;
}
slope = y_intercept = correlation_coef = 0;
if (leastsquares(&src_pixels[block_offset], &bi, chan, i,
&slope, &y_intercept, &correlation_coef)) {
min_color[i] = GET_CHAN(src_pixels[block_offset], i);
max_color[i] = GET_CHAN(src_pixels[block_offset], i);
} else {
tmp_min = (int)(0.5 + min * slope + y_intercept);
tmp_max = (int)(0.5 + max * slope + y_intercept);
av_assert0(tmp_min <= tmp_max);
// clamp min and max color values
tmp_min = av_clip_uint8(tmp_min);
tmp_max = av_clip_uint8(tmp_max);
err = FFMAX(calc_lsq_max_fit_error(&src_pixels[block_offset], &bi,
min, max, tmp_min, tmp_max, chan, i), err);
min_color[i] = tmp_min;
max_color[i] = tmp_max;
}
}
if (err > s->sixteen_color_thresh) { // DO SIXTEEN COLOR BLOCK
const uint16_t *row_ptr;
int y_size, rgb555;
block_offset = get_block_info(&bi, block_counter, 0);
pblock_offset = get_block_info(&bi, block_counter, 1);
row_ptr = &src_pixels[block_offset];
y_size = FFMIN(4, bi.image_height - bi.row * 4);
for (int y = 0; y < y_size; y++) {
for (int x = 0; x < 4; x++) {
rgb555 = row_ptr[x] & ~0x8000;
put_bits(&s->pb, 16, rgb555);
}
row_ptr += bi.rowstride;
}
for (int y = y_size; y < 4; y++) {
for (int x = 0; x < 4; x++)
put_bits(&s->pb, 16, 0);
}
block_counter++;
} else { // FOUR COLOR BLOCK
block_counter += encode_four_color_block(min_color, max_color,
&s->pb, &src_pixels[block_offset], &bi);
}
/* update this block in the previous frame buffer */
update_block_in_prev_frame(&src_pixels[block_offset],
&prev_pixels[pblock_offset], &bi, block_counter);
}
}
}
static int rpza_encode_init(AVCodecContext *avctx)
{
RpzaContext *s = avctx->priv_data;
s->frame_width = avctx->width;
s->frame_height = avctx->height;
s->prev_frame = av_frame_alloc();
if (!s->prev_frame)
return AVERROR(ENOMEM);
return 0;
}
static int rpza_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
const AVFrame *pict, int *got_packet)
{
RpzaContext *s = avctx->priv_data;
uint8_t *buf;
int ret = ff_alloc_packet(avctx, pkt, 4LL + 6LL * avctx->height * avctx->width);
if (ret < 0)
return ret;
init_put_bits(&s->pb, pkt->data, pkt->size);
// skip 4 byte header, write it later once the size of the chunk is known
put_bits32(&s->pb, 0x00);
if (!s->prev_frame->data[0]) {
s->first_frame = 1;
s->prev_frame->format = pict->format;
s->prev_frame->width = pict->width;
s->prev_frame->height = pict->height;
ret = av_frame_get_buffer(s->prev_frame, 0);
if (ret < 0)
return ret;
} else {
s->first_frame = 0;
}
rpza_encode_stream(s, pict);
flush_put_bits(&s->pb);
av_shrink_packet(pkt, put_bytes_output(&s->pb));
buf = pkt->data;
// write header opcode
buf[0] = 0xe1; // chunk opcode
// write chunk length
AV_WB24(buf + 1, pkt->size);
*got_packet = 1;
return 0;
}
static int rpza_encode_end(AVCodecContext *avctx)
{
RpzaContext *s = (RpzaContext *)avctx->priv_data;
av_frame_free(&s->prev_frame);
return 0;
}
#define OFFSET(x) offsetof(RpzaContext, x)
#define VE AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
static const AVOption options[] = {
{ "skip_frame_thresh", NULL, OFFSET(skip_frame_thresh), AV_OPT_TYPE_INT, {.i64=1}, 0, 24, VE},
{ "start_one_color_thresh", NULL, OFFSET(start_one_color_thresh), AV_OPT_TYPE_INT, {.i64=1}, 0, 24, VE},
{ "continue_one_color_thresh", NULL, OFFSET(continue_one_color_thresh), AV_OPT_TYPE_INT, {.i64=0}, 0, 24, VE},
{ "sixteen_color_thresh", NULL, OFFSET(sixteen_color_thresh), AV_OPT_TYPE_INT, {.i64=1}, 0, 24, VE},
{ NULL },
};
static const AVClass rpza_class = {
.class_name = "rpza",
.item_name = av_default_item_name,
.option = options,
.version = LIBAVUTIL_VERSION_INT,
};
const FFCodec ff_rpza_encoder = {
.p.name = "rpza",
CODEC_LONG_NAME("QuickTime video (RPZA)"),
.p.type = AVMEDIA_TYPE_VIDEO,
.p.id = AV_CODEC_ID_RPZA,
.p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE,
.priv_data_size = sizeof(RpzaContext),
.p.priv_class = &rpza_class,
.init = rpza_encode_init,
FF_CODEC_ENCODE_CB(rpza_encode_frame),
.close = rpza_encode_end,
.p.pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_RGB555,
AV_PIX_FMT_NONE},
};