[FFmpeg-devel] [PATCH v1 1/2] lavf/vf_transpose: add exif orientation support
Paul B Mahol
onemda at gmail.com
Mon May 27 10:32:32 EEST 2019
On 5/27/19, Jun Li <junli1026 at gmail.com> wrote:
> On Sun, May 26, 2019 at 2:09 AM Paul B Mahol <onemda at gmail.com> wrote:
>
>> On 5/26/19, Jun Li <junli1026 at gmail.com> wrote:
>> > On Sun, May 26, 2019 at 1:16 AM Paul B Mahol <onemda at gmail.com> wrote:
>> >
>> >> On 5/25/19, Jun Li <junli1026 at gmail.com> wrote:
>> >> > Add exif orientation support and expose an option.
>> >> > ---
>> >> > libavfilter/vf_transpose.c | 258
>> +++++++++++++++++++++++++++++--------
>> >> > 1 file changed, 207 insertions(+), 51 deletions(-)
>> >> >
>> >> > diff --git a/libavfilter/vf_transpose.c b/libavfilter/vf_transpose.c
>> >> > index dd54947bd9..4aebfb9ee4 100644
>> >> > --- a/libavfilter/vf_transpose.c
>> >> > +++ b/libavfilter/vf_transpose.c
>> >> > @@ -46,6 +46,9 @@ typedef struct TransVtable {
>> >> > void (*transpose_block)(uint8_t *src, ptrdiff_t src_linesize,
>> >> > uint8_t *dst, ptrdiff_t dst_linesize,
>> >> > int w, int h);
>> >> > + void (*copyline_block)(uint8_t *src, ptrdiff_t src_linesize,
>> >> > + uint8_t *dst, ptrdiff_t dst_linesize,
>> >> > + int line_dir, int w, int h);
>> >> > } TransVtable;
>> >> >
>> >>
>> >> This is slow, the operations should be in one loop.
>> >>
>> >
>> > Thanks Paul for review.
>> > I see transpose is using " ctx->internal->execute(ctx, filter_slice,
>> > &td,
>> > NULL, FFMIN(outlink->h, ff_filter_get_nb_threads(ctx)));" .
>> > which looks like leveraging multi-threading.
>> > If we do that in one loop, I guess it would be hard to use
>> multi-threading
>> > to accelerate ? But correct me if I am wrong.
>>
>> Transpose filter does one thing and that is transposing.
>>
>> If I'm not mistaken you are adding vertical and horizontal flipping?
>>
>
> Thanks for review.
> Yes, I am doing vflip, hflip and rotate180(vflip+hflip).
>
>
>> If you really need to do that, do it efficiently in one loop, by that I
>> mean
>> you do not do cascading operations at all.
>>
>
> Are you suggesting not use function pointer, and call the function directly
> like this:
Please do not invent things I never said.
I think I was very clear.
But to repeat it once more, it is unacceptable to transpose and do
vflip/hflip as
two separate operations. Instead everything should be done in single pass.
> switch (s->pixsteps[plane]) {
> case 1: copyline_block_8(src, srclinesize, dst,
> dstlinesize, line_dir, outw, end - start); break;
> case 2: copyline_block_16(src, srclinesize, dst,
> dstlinesize, line_dir, outw, end - start); break;
> case 3: copyline_block_24(src, srclinesize, dst,
> dstlinesize, line_dir, outw, end - start); break;
> case 4: copyline_block_32(src, srclinesize, dst,
> dstlinesize, line_dir, outw, end - start); break;
> case 6: copyline_block_48(src, srclinesize, dst,
> dstlinesize, line_dir, outw, end - start); break;
> case 8: copyline_block_64(src, srclinesize, dst,
> dstlinesize, line_dir, outw, end - start); break;
> }
>
> I did some perf comparsion, they are very close and no significant
> difference, about 9ms for one frame.
>
> Also I did some comparison between current hflip filter and this patch,
> they take almost the same time, about 9ms too on my machine and I see 13
> threads/jobs are used for filtering.
> I just use the simple command "ffmpeg -i test.bmp -vf
> transpose=orientation=2 -y hello.jpg".
> Current vflip wins a lot and I see it is not copying frame at all, just
> like "orientation=1" or "passthrough" cases.
>
> I hope I understand you correctly, especially about "cascading operations".
> But correct me if I am wrong.
> Thanks for your time Paul.
>
> Best Regards,
> -Jun
>
>>
>> > Best Regards,
>> > -Jun
>> >
>> >
>> >> > typedef struct TransContext {
>> >> > @@ -56,7 +59,7 @@ typedef struct TransContext {
>> >> >
>> >> > int passthrough; ///< PassthroughType, landscape passthrough
>> >> > mode
>> >> > enabled
>> >> > int dir; ///< TransposeDir
>> >> > -
>> >> > + int orientation; ///< Orientation
>> >> > TransVtable vtables[4];
>> >> > } TransContext;
>> >> >
>> >> > @@ -182,6 +185,105 @@ static void transpose_8x8_64_c(uint8_t *src,
>> >> ptrdiff_t
>> >> > src_linesize,
>> >> > transpose_block_64_c(src, src_linesize, dst, dst_linesize, 8,
>> >> > 8);
>> >> > }
>> >> >
>> >> > +
>> >> > +static void copyline_block_8(uint8_t *src, ptrdiff_t src_linesize,
>> >> > + uint8_t *dst, ptrdiff_t dst_linesize,
>> >> > + int line_dir, int w, int h)
>> >> > +{
>> >> > + int x, y, i;
>> >> > + for (y = 0; y < h; y++, dst += dst_linesize, src +=
>> src_linesize) {
>> >> > + for (x = 0; x < w; x ++) {
>> >> > + i = line_dir < 0 ? w-x-1 : x;
>> >> > + dst[i] = src[x];
>> >> > + }
>> >> > + }
>> >> > +}
>> >> > +
>> >> > +static void copyline_block_16(uint8_t *src, ptrdiff_t src_linesize,
>> >> > + uint8_t *dst, ptrdiff_t dst_linesize,
>> >> > + int line_dir, int w, int h)
>> >> > +{
>> >> > + int x, y, i;
>> >> > + for (y = 0; y < h; y++, dst += dst_linesize, src +=
>> src_linesize) {
>> >> > + for (x = 0; x < w; x ++) {
>> >> > + i = line_dir < 0 ? w-x-1 : x;
>> >> > + *((uint16_t *)(dst + 2*i)) = *((uint16_t *)(src + 2*x));
>> >> > + }
>> >> > + }
>> >> > +}
>> >> > +
>> >> > +static void copyline_block_24(uint8_t *src, ptrdiff_t src_linesize,
>> >> > + uint8_t *dst, ptrdiff_t dst_linesize,
>> >> > + int line_dir, int w, int h)
>> >> > +{
>> >> > + int x, y, i;
>> >> > + for (y = 0; y < h; y++, dst += dst_linesize, src +=
>> src_linesize) {
>> >> > + for (x = 0; x < w; x++) {
>> >> > + int32_t v = AV_RB24(src + 3*x);
>> >> > + i = line_dir < 0 ? w-x-1 : x;
>> >> > + AV_WB24(dst + 3*i, v);
>> >> > + }
>> >> > + }
>> >> > +}
>> >> > +
>> >> > +static void copyline_block_32(uint8_t *src, ptrdiff_t src_linesize,
>> >> > + uint8_t *dst, ptrdiff_t dst_linesize,
>> >> > + int line_dir, int w, int h)
>> >> > +{
>> >> > + int x, y, i;
>> >> > + for (y = 0; y < h; y++, dst += dst_linesize, src +=
>> src_linesize) {
>> >> > + for (x = 0; x < w; x ++) {
>> >> > + i = line_dir < 0 ? w-x-1 : x;
>> >> > + *((uint32_t *)(dst + 4*i)) = *((uint32_t *)(src + 4*x));
>> >> > + }
>> >> > + }
>> >> > +}
>> >> > +
>> >> > +static void copyline_block_48(uint8_t *src, ptrdiff_t src_linesize,
>> >> > + uint8_t *dst, ptrdiff_t dst_linesize,
>> >> > + int line_dir, int w, int h)
>> >> > +{
>> >> > + int x, y, i;
>> >> > + for (y = 0; y < h; y++, dst += dst_linesize, src +=
>> src_linesize) {
>> >> > + for (x = 0; x < w; x++) {
>> >> > + int64_t v = AV_RB48(src + 6*x);
>> >> > + i = line_dir < 0 ? w-x-1 : x;
>> >> > + AV_WB48(dst + 6*i, v);
>> >> > + }
>> >> > + }
>> >> > +}
>> >> > +
>> >> > +static void copyline_block_64(uint8_t *src, ptrdiff_t src_linesize,
>> >> > + uint8_t *dst, ptrdiff_t dst_linesize,
>> >> > + int line_dir, int w, int h)
>> >> > +{
>> >> > + int x, y, i;
>> >> > + for (y = 0; y < h; y++, dst += dst_linesize, src +=
>> src_linesize) {
>> >> > + for (x = 0; x < w; x ++) {
>> >> > + i = line_dir < 0 ? w-x-1 : x;
>> >> > + *((uint64_t *)(dst + 8*i)) = *((uint64_t *)(src + 8*x));
>> >> > + }
>> >> > + }
>> >> > +}
>> >> > +
>> >> > +static void set_outlink_width_height(AVFilterLink *inlink,
>> AVFilterLink
>> >> > *outlink, int transpose)
>> >> > +{
>> >> > + if (transpose) {
>> >> > + outlink->w = inlink->h;
>> >> > + outlink->h = inlink->w;
>> >> > +
>> >> > + if (inlink->sample_aspect_ratio.num)
>> >> > + outlink->sample_aspect_ratio = av_div_q((AVRational) {
>> 1, 1
>> >> },
>> >> > +
>> >> > inlink->sample_aspect_ratio);
>> >> > + else
>> >> > + outlink->sample_aspect_ratio =
>> inlink->sample_aspect_ratio;
>> >> > + } else {
>> >> > + outlink->w = inlink->w;
>> >> > + outlink->h = inlink->h;
>> >> > + outlink->sample_aspect_ratio = inlink->sample_aspect_ratio;
>> >> > + }
>> >> > +}
>> >> > +
>> >> > static int config_props_output(AVFilterLink *outlink)
>> >> > {
>> >> > AVFilterContext *ctx = outlink->src;
>> >> > @@ -213,33 +315,44 @@ static int config_props_output(AVFilterLink
>> >> *outlink)
>> >> >
>> >> > av_assert0(desc_in->nb_components == desc_out->nb_components);
>> >> >
>> >> > -
>> >> > av_image_fill_max_pixsteps(s->pixsteps, NULL, desc_out);
>> >> > +
>> >> > + if (s->orientation && s->orientation < 5) {
>> >> > + outlink->h = inlink->h;
>> >> > + outlink->w = inlink->w;
>> >> > + outlink->sample_aspect_ratio = inlink->sample_aspect_ratio;
>> >> > + } else {
>> >> > + outlink->w = inlink->h;
>> >> > + outlink->h = inlink->w;
>> >> >
>> >> > - outlink->w = inlink->h;
>> >> > - outlink->h = inlink->w;
>> >> > -
>> >> > - if (inlink->sample_aspect_ratio.num)
>> >> > - outlink->sample_aspect_ratio = av_div_q((AVRational) { 1, 1
>> },
>> >> > -
>> >> > inlink->sample_aspect_ratio);
>> >> > - else
>> >> > - outlink->sample_aspect_ratio = inlink->sample_aspect_ratio;
>> >> > + if (inlink->sample_aspect_ratio.num)
>> >> > + outlink->sample_aspect_ratio = av_div_q((AVRational) {
>> 1, 1
>> >> },
>> >> > +
>> >> > inlink->sample_aspect_ratio);
>> >> > + else
>> >> > + outlink->sample_aspect_ratio =
>> inlink->sample_aspect_ratio;
>> >> > + }
>> >> >
>> >> > for (int i = 0; i < 4; i++) {
>> >> > TransVtable *v = &s->vtables[i];
>> >> > switch (s->pixsteps[i]) {
>> >> > case 1: v->transpose_block = transpose_block_8_c;
>> >> > - v->transpose_8x8 = transpose_8x8_8_c; break;
>> >> > + v->transpose_8x8 = transpose_8x8_8_c;
>> >> > + v->copyline_block = copyline_block_8; break;
>> >> > case 2: v->transpose_block = transpose_block_16_c;
>> >> > - v->transpose_8x8 = transpose_8x8_16_c; break;
>> >> > + v->transpose_8x8 = transpose_8x8_16_c;
>> >> > + v->copyline_block = copyline_block_16; break;
>> >> > case 3: v->transpose_block = transpose_block_24_c;
>> >> > - v->transpose_8x8 = transpose_8x8_24_c; break;
>> >> > + v->transpose_8x8 = transpose_8x8_24_c;
>> >> > + v->copyline_block = copyline_block_24; break;
>> >> > case 4: v->transpose_block = transpose_block_32_c;
>> >> > - v->transpose_8x8 = transpose_8x8_32_c; break;
>> >> > + v->transpose_8x8 = transpose_8x8_32_c;
>> >> > + v->copyline_block = copyline_block_32; break;
>> >> > case 6: v->transpose_block = transpose_block_48_c;
>> >> > - v->transpose_8x8 = transpose_8x8_48_c; break;
>> >> > + v->transpose_8x8 = transpose_8x8_48_c;
>> >> > + v->copyline_block = copyline_block_48; break;
>> >> > case 8: v->transpose_block = transpose_block_64_c;
>> >> > - v->transpose_8x8 = transpose_8x8_64_c; break;
>> >> > + v->transpose_8x8 = transpose_8x8_64_c;
>> >> > + v->copyline_block = copyline_block_64; break;
>> >> > }
>> >> > }
>> >> >
>> >> > @@ -285,42 +398,80 @@ static int filter_slice(AVFilterContext *ctx,
>> void
>> >> > *arg, int jobnr,
>> >> > uint8_t *dst, *src;
>> >> > int dstlinesize, srclinesize;
>> >> > int x, y;
>> >> > + int dir = s->dir;
>> >> > TransVtable *v = &s->vtables[plane];
>> >> > +
>> >> > + if (s->orientation > 0 && s->orientation < 5) {
>> >> > + int line_dir = 1;
>> >> > + dstlinesize = out->linesize[plane];
>> >> > + dst = out->data[plane] + start * dstlinesize;
>> >> > + srclinesize = in->linesize[plane];
>> >> > + src = in->data[plane] + start * srclinesize;
>> >> > +
>> >> > + switch (s->orientation) {
>> >> > + case 2: // mirror horizontal
>> >> > + line_dir = -1;
>> >> > + break;
>> >> > + case 3: // rotate 180
>> >> > + dst = out->data[plane] + (outh - start
>> >> > -
>> >> 1) *
>> >> > dstlinesize;
>> >> > + line_dir = -1;
>> >> > + dstlinesize *= -1;
>> >> > + break;
>> >> > + case 4: // mirror vertical
>> >> > + dst = out->data[plane] + (outh - start
>> >> > -
>> >> 1) *
>> >> > dstlinesize;
>> >> > + dstlinesize *= -1;
>> >> > + break;
>> >> > + default:
>> >> > + break;
>> >> > + }
>> >> > + v->copyline_block(src, srclinesize, dst, dstlinesize,
>> >> line_dir,
>> >> > outw, end - start);
>> >> > + } else {
>> >> > + dstlinesize = out->linesize[plane];
>> >> > + dst = out->data[plane] + start * dstlinesize;
>> >> > + src = in->data[plane];
>> >> > + srclinesize = in->linesize[plane];
>> >> > + switch (s->orientation) {
>> >> > + case 5: // mirror horizontal and rotate 270 CW
>> >> > + dir = 0; break;
>> >> > + case 6: // rotate 90 CW
>> >> > + dir = 1; break;
>> >> > + case 7: // mirror horizontal and rotate 90 CW
>> >> > + dir = 3; break;
>> >> > + case 8: // rotate 270 CW
>> >> > + dir = 2; break;
>> >> > + default: break;
>> >> > + }
>> >> >
>> >> > - dstlinesize = out->linesize[plane];
>> >> > - dst = out->data[plane] + start * dstlinesize;
>> >> > - src = in->data[plane];
>> >> > - srclinesize = in->linesize[plane];
>> >> > -
>> >> > - if (s->dir & 1) {
>> >> > - src += in->linesize[plane] * (inh - 1);
>> >> > - srclinesize *= -1;
>> >> > - }
>> >> > + if (dir & 1) {
>> >> > + src += in->linesize[plane] * (inh - 1);
>> >> > + srclinesize *= -1;
>> >> > + }
>> >> >
>> >> > - if (s->dir & 2) {
>> >> > - dst = out->data[plane] + dstlinesize * (outh -
>> >> start -
>> >> > 1);
>> >> > - dstlinesize *= -1;
>> >> > - }
>> >> > + if (dir & 2) {
>> >> > + dst = out->data[plane] + dstlinesize *
>> (outh -
>> >> > start - 1);
>> >> > + dstlinesize *= -1;
>> >> > + }
>> >> >
>> >> > - for (y = start; y < end - 7; y += 8) {
>> >> > - for (x = 0; x < outw - 7; x += 8) {
>> >> > - v->transpose_8x8(src + x * srclinesize + y *
>> >> > pixstep,
>> >> > - srclinesize,
>> >> > - dst + (y - start) * dstlinesize + x
>> *
>> >> > pixstep,
>> >> > - dstlinesize);
>> >> > + for (y = start; y < end - 7; y += 8) {
>> >> > + for (x = 0; x < outw - 7; x += 8) {
>> >> > + v->transpose_8x8(src + x * srclinesize + y *
>> >> pixstep,
>> >> > + srclinesize,
>> >> > + dst + (y - start) * dstlinesize
>> + x
>> >> *
>> >> > pixstep,
>> >> > + dstlinesize);
>> >> > + }
>> >> > + if (outw - x > 0 && end - y > 0)
>> >> > + v->transpose_block(src + x * srclinesize + y *
>> >> pixstep,
>> >> > + srclinesize,
>> >> > + dst + (y - start) * dstlinesize
>> + x
>> >> *
>> >> > pixstep,
>> >> > + dstlinesize, outw - x, end - y);
>> >> > }
>> >> > - if (outw - x > 0 && end - y > 0)
>> >> > - v->transpose_block(src + x * srclinesize + y *
>> pixstep,
>> >> > - srclinesize,
>> >> > - dst + (y - start) * dstlinesize +
>> x
>> >> > *
>> >> > pixstep,
>> >> > - dstlinesize, outw - x, end - y);
>> >> > - }
>> >> >
>> >> > - if (end - y > 0)
>> >> > - v->transpose_block(src + 0 * srclinesize + y * pixstep,
>> >> > - srclinesize,
>> >> > - dst + (y - start) * dstlinesize + 0 *
>> >> > pixstep,
>> >> > - dstlinesize, outw, end - y);
>> >> > + if (end - y > 0)
>> >> > + v->transpose_block(src + 0 * srclinesize + y *
>> pixstep,
>> >> > + srclinesize,
>> >> > + dst + (y - start) * dstlinesize + 0
>> >> > *
>> >> > pixstep,
>> >> > + dstlinesize, outw, end - y);
>> >> > + }
>> >> > }
>> >> >
>> >> > return 0;
>> >> > @@ -334,7 +485,7 @@ static int filter_frame(AVFilterLink *inlink,
>> >> > AVFrame
>> >> > *in)
>> >> > ThreadData td;
>> >> > AVFrame *out;
>> >> >
>> >> > - if (s->passthrough)
>> >> > + if (s->passthrough || s->orientation == 1)
>> >> > return ff_filter_frame(outlink, in);
>> >> >
>> >> > out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
>> >> > @@ -347,8 +498,13 @@ static int filter_frame(AVFilterLink *inlink,
>> >> AVFrame
>> >> > *in)
>> >> > if (in->sample_aspect_ratio.num == 0) {
>> >> > out->sample_aspect_ratio = in->sample_aspect_ratio;
>> >> > } else {
>> >> > - out->sample_aspect_ratio.num = in->sample_aspect_ratio.den;
>> >> > - out->sample_aspect_ratio.den = in->sample_aspect_ratio.num;
>> >> > + if (s->orientation > 0 && s->orientation < 5) {
>> >> > + out->sample_aspect_ratio.num =
>> in->sample_aspect_ratio.num;
>> >> > + out->sample_aspect_ratio.den =
>> in->sample_aspect_ratio.den;
>> >> > + } else {
>> >> > + out->sample_aspect_ratio.num =
>> in->sample_aspect_ratio.den;
>> >> > + out->sample_aspect_ratio.den =
>> in->sample_aspect_ratio.num;
>> >> > + }
>> >> > }
>> >> >
>> >> > td.in = in, td.out = out;
>> >> > @@ -366,13 +522,13 @@ static const AVOption transpose_options[] = {
>> >> > { "clock", "rotate clockwise",
>> >> 0,
>> >> > AV_OPT_TYPE_CONST, { .i64 = TRANSPOSE_CLOCK }, .flags=FLAGS,
>> .unit
>> >> =
>> >> > "dir" },
>> >> > { "cclock", "rotate counter-clockwise",
>> >> 0,
>> >> > AV_OPT_TYPE_CONST, { .i64 = TRANSPOSE_CCLOCK }, .flags=FLAGS,
>> .unit
>> >> =
>> >> > "dir" },
>> >> > { "clock_flip", "rotate clockwise with vertical flip",
>> >> 0,
>> >> > AV_OPT_TYPE_CONST, { .i64 = TRANSPOSE_CLOCK_FLIP }, .flags=FLAGS,
>> .unit
>> >> =
>> >> > "dir" },
>> >> > -
>> >> > +
>> >> > { "passthrough", "do not apply transposition if the input
>> >> > matches
>> >> the
>> >> > specified geometry",
>> >> > OFFSET(passthrough), AV_OPT_TYPE_INT,
>> >> {.i64=TRANSPOSE_PT_TYPE_NONE},
>> >> > 0, INT_MAX, FLAGS, "passthrough" },
>> >> > { "none", "always apply transposition", 0,
>> >> > AV_OPT_TYPE_CONST, {.i64=TRANSPOSE_PT_TYPE_NONE}, INT_MIN,
>> INT_MAX,
>> >> > FLAGS, "passthrough" },
>> >> > { "portrait", "preserve portrait geometry", 0,
>> >> > AV_OPT_TYPE_CONST, {.i64=TRANSPOSE_PT_TYPE_PORTRAIT}, INT_MIN,
>> INT_MAX,
>> >> > FLAGS, "passthrough" },
>> >> > { "landscape", "preserve landscape geometry", 0,
>> >> > AV_OPT_TYPE_CONST, {.i64=TRANSPOSE_PT_TYPE_LANDSCAPE}, INT_MIN,
>> INT_MAX,
>> >> > FLAGS, "passthrough" },
>> >> > -
>> >> > + { "orientation", "set exif orientation", OFFSET(orientation),
>> >> > AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 8, FLAGS, "orientation" },
>> >> > { NULL }
>> >> > };
>> >> >
>> >> > --
>> >> > 2.17.1
>> >> >
>> >> > _______________________________________________
>> >> > ffmpeg-devel mailing list
>> >> > ffmpeg-devel at ffmpeg.org
>> >> > https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
>> >> >
>> >> > To unsubscribe, visit link above, or email
>> >> > ffmpeg-devel-request at ffmpeg.org with subject "unsubscribe".
>> >> _______________________________________________
>> >> ffmpeg-devel mailing list
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>> >> https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
>> >>
>> >> To unsubscribe, visit link above, or email
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>> > _______________________________________________
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